Started rewriting math screen and conversion logics

.classpath

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry excluding="org/warp/picalculator/deprecatedmath/|org/warp/picalculator/device/PIDisplay.java|org/warp/picalculator/device/graphicengine/Display.java" kind="src" path="src"/>
+	<classpathentry excluding="org/warp/picalculator/deprecatedmath/|org/warp/picalculator/device/PIDisplay.java|org/warp/picalculator/device/graphicengine/Display.java|com/rits/cloning/|com/rits/perspectives/|com/rits/|com/|org/warp/picalculator/TestCalcBenchmark.java" kind="src" path="src"/>
 	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
 	<classpathentry kind="src" path="res"/>
 	<classpathentry exported="true" kind="con" path="org.eclipse.jdt.USER_LIBRARY/JOGL"/>

src/org/warp/picalculator/BMPFile.java

@@ -116,8 +116,7 @@ public class BMPFile extends Component {
 		final byte rgb[] = new byte[3];
 		size = (biWidth * biHeight) - 1;
 		pad = 4 - ((biWidth * 3) % 4);
-		if (pad == 4)
+		if (pad == 4) {
-		 {
 			pad = 0; // <==== Bug correction
 		}
 		rowCount = 1;

src/org/warp/picalculator/Main.java

@@ -14,6 +14,9 @@ public class Main {
 	public static Main instance;
 	public static boolean haxMode = true;
 	public static String[] args;
+	public static final String calculatorName = "WarpPI";
+	public static final String calculatorNameLOWER = "warppi";
+	public static final String calculatorNameUPPER = "WARPPI";
 
 	public Main(String[] args) throws InterruptedException {
 		this(new LoadingScreen(), args);
@@ -23,7 +26,7 @@ public class Main {
 		instance = this;
 		Thread.currentThread().setPriority(Thread.MAX_PRIORITY);
 		Thread.currentThread().setName("Main thread");
-		this.args = args;
+		Main.args = args;
 		beforeStart();
 		new DisplayManager(screen);
 		Utils.debug.println("Shutdown...");

src/org/warp/picalculator/TestCalcBenchmark.java

@@ -7,22 +7,22 @@ public class TestCalcBenchmark {
 
 	public static void main(String[] args) throws Error {
 		Utils.debugOn = true;
-		int times = 1;
+		final int times = 1;
 
-		MathContext mc = new MathContext();
+		final MathContext mc = new MathContext();
-		long time1 = System.nanoTime();
+		final long time1 = System.nanoTime();
 		mc.parseInputString("5WABCDEFGHIWABCDEFGHIWABCDEFGHIWABCDEFGHIWABCDEFGHIWABCDEFGHI");
-		long time2 = System.nanoTime();
+		final long time2 = System.nanoTime();
 		for (int i = 0; i < times; i++) {
 			if (i == 1) {
 				Utils.debugOn = false;
 			}
 			mc.f2 = mc.solveExpression(mc.f);
 		}
-		long time3 = System.nanoTime();
+		final long time3 = System.nanoTime();
 //		System.out.println(mc.f2.get(0).toString());
-		System.out.println("PARSING\t"+((time2-time1) / 1000000d / ((double) times)) + " milliseconds");
+		System.out.println("PARSING\t" + ((time2 - time1) / 1000000d / (times)) + " milliseconds");
-		System.out.println("WORK\t"+((time3-time2) / 1000000d / ((double) times)) + " milliseconds");
+		System.out.println("WORK\t" + ((time3 - time2) / 1000000d / (times)) + " milliseconds");
-		System.out.println("TOTAL\t"+((time3-time1) / 1000000d / ((double) times)) + " milliseconds");
+		System.out.println("TOTAL\t" + ((time3 - time1) / 1000000d / (times)) + " milliseconds");
 	}
 }

src/org/warp/picalculator/TestDrivers.java

@@ -23,7 +23,7 @@ public class TestDrivers {
 		try {
 			Class.forName(className);
 			return true;
-		} catch( ClassNotFoundException e ) {
+		} catch (final ClassNotFoundException e) {
 			return false;
 		}
 	}

src/org/warp/picalculator/TestGPU.java

@@ -8,17 +8,14 @@ import org.warp.picalculator.gui.graphicengine.RenderingLoop;
 import org.warp.picalculator.device.Keyboard;
 import org.warp.picalculator.device.Keyboard.Key;
 import org.warp.picalculator.device.KeyboardEventListener;
-import org.warp.picalculator.gui.GUIErrorMessage;
 import org.warp.picalculator.gui.expression.BlockContainer;
 import org.warp.picalculator.gui.expression.containers.NormalInputContainer;
 import org.warp.picalculator.gui.graphicengine.BinaryFont;
 import org.warp.picalculator.gui.graphicengine.Skin;
-import org.warp.picalculator.gui.graphicengine.cpu.CPUEngine;
 import org.warp.picalculator.gui.graphicengine.gpu.GPUEngine;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.functions.Expression;
-import org.warp.picalculator.math.functions.Root;
 import org.warp.picalculator.math.parser.MathParser;
 
 public class TestGPU {
@@ -107,9 +104,9 @@ public class TestGPU {
 					case EQUAL:
 						Expression expr;
 						try {
-							expr = MathParser.parseInput(new MathContext(), c.root);
+							expr = MathParser.parseInput(new MathContext(), c);
 							System.out.println("Parsed input:" + expr.toString());
-						} catch (Error e) {
+						} catch (final Error e) {
 							e.printStackTrace();
 						}
 				}
@@ -131,7 +128,7 @@ public class TestGPU {
 
 	private static class Scene implements RenderingLoop {
 
-		private BinaryFont exampleFont;
+		private final BinaryFont exampleFont;
 		private final Skin exampleSkin;
 
 		private final Renderer r;
@@ -148,7 +145,6 @@ public class TestGPU {
 
 			BlockContainer.initializeFonts(d.loadFont("ex"), d.loadFont("big"));
 
-
 			//New expression framework test
 			c = new NormalInputContainer(false, 0, 200);
 			c.typeChar(MathematicalSymbols.DIVISION);
@@ -209,7 +205,7 @@ public class TestGPU {
 			if (lastTime == 0) {
 				lastTime = System.currentTimeMillis();
 			}
-			double delta = System.currentTimeMillis()-lastTime;
+			final double delta = System.currentTimeMillis() - lastTime;
 			lastTime = System.currentTimeMillis();
 			c.beforeRender((float) (delta / 1000d));
 			c.draw(d, r, 10, 220);

src/org/warp/picalculator/Utils.java

@@ -37,8 +37,6 @@ import org.warp.picalculator.math.functions.Variable;
 import org.warp.picalculator.math.functions.equations.Equation;
 import org.warp.picalculator.math.functions.equations.EquationsSystemPart;
 
-import com.rits.cloning.Cloner;
-
 public class Utils {
 
 	public static final int scale = 24;
@@ -52,8 +50,6 @@ public class Utils {
 	public static boolean debugOn;
 	public static boolean debugThirdScreen;
 
-	public static Cloner cloner = new Cloner();
-
 	public static final class DebugStream extends StringWriter {
 
 		public void println(String str) {
@@ -198,7 +194,8 @@ public class Utils {
 		return true;
 	}
 
-	public static boolean areThereOnlySettedUpFunctionsSumsMultiplicationsEquationsAndSystems(ObjectArrayList<Function> fl) {
+	public static boolean areThereOnlySettedUpFunctionsSumsMultiplicationsEquationsAndSystems(
+			ObjectArrayList<Function> fl) {
 		for (int i = 0; i < fl.size(); i++) {
 			if (!(fl.get(i) instanceof Number || fl.get(i) instanceof Variable || fl.get(i) instanceof Multiplication || fl.get(i) instanceof Sum || fl.get(i) instanceof SumSubtraction || fl.get(i) instanceof Subtraction || fl.get(i) instanceof Equation || fl.get(i) instanceof EquationsSystemPart || fl.get(i) instanceof Expression)) {
 				if (fl.get(i) instanceof FunctionSingle) {
@@ -537,13 +534,12 @@ public class Utils {
 		return results;
 	}
 
-
 	public static Function[][] joinFunctionsResults(ObjectArrayList<ObjectArrayList<Function>> ln) {
 		final int[] sizes = new int[ln.size()];
 		for (int i = 0; i < ln.size(); i++) {
 			sizes[i] = ln.get(i).size();
 		}
-		int[] curs = new int[sizes.length];
+		final int[] curs = new int[sizes.length];
 		int total = 0;
 		for (int i = 0; i < ln.size(); i++) {
 			if (i == 0) {
@@ -615,27 +611,27 @@ public class Utils {
 
 	public static void printSystemResourcesUsage() {
 		System.out.println("============");
-		OperatingSystemMXBean operatingSystemMXBean = ManagementFactory.getOperatingSystemMXBean();
+		final OperatingSystemMXBean operatingSystemMXBean = ManagementFactory.getOperatingSystemMXBean();
-		for (Method method : operatingSystemMXBean.getClass().getDeclaredMethods()) {
+		for (final Method method : operatingSystemMXBean.getClass().getDeclaredMethods()) {
 			method.setAccessible(true);
 			if (method.getName().startsWith("get") && Modifier.isPublic(method.getModifiers())) {
 				Object value;
 				try {
 					value = method.invoke(operatingSystemMXBean);
-				} catch (Exception e) {
+				} catch (final Exception e) {
 					value = e;
 				} // try
 				boolean percent = false;
 				boolean mb = false;
-				String displayName = method.getName();
+				final String displayName = method.getName();
-				String displayValue = value.toString();
+				final String displayValue = value.toString();
 				if (displayName.endsWith("CpuLoad")) {
 					percent = true;
 				}
 				if (displayName.endsWith("MemorySize")) {
 					mb = true;
 				}
-				ObjectArrayList<String> arr = new ObjectArrayList<>();
+				final ObjectArrayList<String> arr = new ObjectArrayList<>();
 				arr.add("getFreePhysicalMemorySize");
 				arr.add("getProcessCpuLoad");
 				arr.add("getSystemCpuLoad");
@@ -644,13 +640,13 @@ public class Utils {
 					if (percent) {
 						try {
 							System.out.println(displayName + " = " + (((int) (Float.parseFloat(displayValue) * 10000f)) / 100f) + "%");
-						}catch(Exception ex) {
+						} catch (final Exception ex) {
 							System.out.println(displayName + " = " + displayValue);
 						}
 					} else if (mb) {
 						try {
 							System.out.println(displayName + " = " + (Long.parseLong(displayValue) / 1024L / 1024L) + " MB");
-						}catch(Exception ex) {
+						} catch (final Exception ex) {
 							System.out.println(displayName + " = " + displayValue);
 						}
 					} else {
@@ -665,8 +661,7 @@ public class Utils {
 	public static boolean isRunningOnRaspberry() {
 		if (System.getProperty("os.name").equals("Linux")) {
 			final File file = new File("/etc", "os-release");
-	        try (FileInputStream fis = new FileInputStream(file);
+			try (FileInputStream fis = new FileInputStream(file); BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(fis))) {
-	             BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(fis))) {
 				String string;
 				while ((string = bufferedReader.readLine()) != null) {
 					if (string.toLowerCase().contains("raspbian")) {

src/org/warp/picalculator/device/CacheFile.java

@@ -0,0 +1,88 @@
+package org.warp.picalculator.device;
+
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.UUID;
+
+import org.warp.picalculator.Main;
+
+public class CacheFile {
+	private String path;
+	private ObjectOutputStream lastOOS;
+	private FileOutputStream lastFOS;
+	private ObjectInputStream lastOIS;
+	private FileInputStream lastFIS;
+	
+	public CacheFile() {
+		do {
+			path = UUID.randomUUID().toString()+".ser";
+		} while (Files.exists(Paths.get(path)));
+		try {
+			Files.createTempFile(Main.calculatorNameLOWER, "");
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+	}
+	
+	public ObjectOutputStream getObjectOutputStram() {
+		if (lastOOS == null) {
+			try {
+				return new ObjectOutputStream(new FileOutputStream(path));
+			} catch (IOException e) {
+				e.printStackTrace();
+				return lastOOS;
+			}
+		} else {
+			return lastOOS;
+		}
+	}
+	
+	public ObjectInputStream getObjectInputStram() {
+		if (lastOIS == null) {
+			try {
+				return new ObjectInputStream(new FileInputStream(path));
+			} catch (IOException e) {
+				return lastOIS;
+			}
+		} else {
+			return lastOIS;
+		}
+	}
+
+	public void closeStreams() {
+		try {
+			if (lastOOS != null) {
+				lastOOS.close();
+				lastOOS = null;
+			}
+			if (lastFOS != null) {
+				lastFOS.close();
+				lastFOS = null;
+			}
+			if (lastOIS != null) {
+				lastOIS.close();
+				lastOIS = null;
+			}
+			if (lastFIS != null) {
+				lastFIS.close();
+				lastFIS = null;
+			}
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+	}
+
+	public void dispose() {
+		closeStreams();
+		try {
+			Files.deleteIfExists(Paths.get(path));
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+	}
+}

src/org/warp/picalculator/device/Keyboard.java

@@ -703,7 +703,7 @@ public class Keyboard {
 		if (additionalListener != null) {
 			try {
 				done = additionalListener.keyPressed(k);
-			} catch (Exception ex) {
+			} catch (final Exception ex) {
 				new GUIErrorMessage(ex);
 			}
 		}
@@ -713,7 +713,7 @@ public class Keyboard {
 			boolean scrdone = false;
 			try {
 				scrdone = scr.keyPressed(k);
-			} catch (Exception ex) {
+			} catch (final Exception ex) {
 				new GUIErrorMessage(ex);
 			}
 			if (scr != null && scr.initialized && scrdone) {

src/org/warp/picalculator/device/graphicengine/RAWFont.java

@@ -33,13 +33,13 @@ public class RAWFont {
 	public void create(String name) {
 		try {
 			loadFont("/font_" + name + ".rft");
-		} catch (IOException e) {
+		} catch (final IOException e) {
 			e.printStackTrace();
 			System.exit(1);
 		}
 		chars32 = new int[(maxBound - minBound) * charIntCount];
 		for (int charIndex = 0; charIndex < maxBound - minBound; charIndex++) {
-            boolean[] currentChar = rawchars[charIndex];
+			final boolean[] currentChar = rawchars[charIndex];
 			if (currentChar == null) {
 				int currentInt = 0;
 				int currentBit = 0;
@@ -66,7 +66,7 @@ public class RAWFont {
 		}
 
 		Object obj = new Object();
-        WeakReference<Object> ref = new WeakReference<>(obj);
+		final WeakReference<Object> ref = new WeakReference<>(obj);
 		obj = null;
 		while (ref.get() != null) {
 			System.gc();
@@ -74,9 +74,9 @@ public class RAWFont {
 	}
 
 	private void loadFont(String string) throws IOException {
-		URL res = Main.instance.getClass().getResource(string);
+		final URL res = Main.instance.getClass().getResource(string);
-		int[] file = Utils.realBytes(Utils.convertStreamToByteArray(res.openStream(), res.getFile().length()));
+		final int[] file = Utils.realBytes(Utils.convertStreamToByteArray(res.openStream(), res.getFile().length()));
-		int filelength = file.length;
+		final int filelength = file.length;
 		if (filelength >= 16) {
 			if (file[0x0] == 114 && file[0x1] == 97 && file[0x2] == 119 && file[0x3] == 0xFF && file[0x8] == 0xFF && file[0xD] == 0xFF) {
 				charW = file[0x4] << 8 | file[0x5];
@@ -92,8 +92,8 @@ public class RAWFont {
 				int index = 0x12;
 				while (index < filelength) {
 					try {
-			        	int charIndex = file[index] << 8 | file[index+1];
+						final int charIndex = file[index] << 8 | file[index + 1];
-			        	boolean[] rawchar = new boolean[charS];
+						final boolean[] rawchar = new boolean[charS];
 						int charbytescount = 0;
 						while (charbytescount * 8 < charS) {
 							charbytescount += 1;
@@ -110,8 +110,7 @@ public class RAWFont {
 						}
 						rawchars[charIndex - minBound] = rawchar;
 						index += 2 + charbytescount;
-		        	}
+					} catch (final Exception ex) {
-	        		catch (Exception ex) {
 						ex.printStackTrace();
 						System.out.println(string);
 						System.exit(-1);
@@ -127,8 +126,8 @@ public class RAWFont {
 
 	public int[] getCharIndexes(String txt) {
 		final int l = txt.length();
-        int[] indexes = new int[l];
+		final int[] indexes = new int[l];
-        char[] chars = txt.toCharArray();
+		final char[] chars = txt.toCharArray();
 		for (int i = 0; i < l; i++) {
 			indexes[i] = (chars[i] & 0xFFFF) - minBound;
 		}
@@ -137,12 +136,12 @@ public class RAWFont {
 
 	@SuppressWarnings("unused")
 	private void saveArray(int[] screen, String coutputpng) {
-        BufferedImage bi = new BufferedImage(300, 200, BufferedImage.TYPE_INT_RGB);
+		final BufferedImage bi = new BufferedImage(300, 200, BufferedImage.TYPE_INT_RGB);
 		final int[] a = ((DataBufferInt) bi.getRaster().getDataBuffer()).getData();
 		System.arraycopy(screen, 0, a, 0, screen.length);
 		try {
 			ImageIO.write(bi, "PNG", new File(coutputpng));
-        } catch (IOException ex) {
+		} catch (final IOException ex) {
 			Logger.getLogger(RAWFont.class.getName()).log(Level.SEVERE, null, ex);
 		}
 	}
@@ -151,7 +150,6 @@ public class RAWFont {
 		final int screenLength = screen.length;
 		int screenPos = 0;
 
-        
 		int currentInt;
 		int currentIntBitPosition;
 		int bitData;
@@ -165,7 +163,7 @@ public class RAWFont {
 				for (int dx = 0; dx < charW; dx++) {
 					j = x + cpos + dx;
 					if (j > 0 & j < screenSize[0]) {
-                        int bit = dx + dy * charW;
+						final int bit = dx + dy * charW;
 						currentInt = (int) (Math.floor(bit) / (intBits));
 						currentIntBitPosition = bit - (currentInt * intBits);
 						bitData = (chars32[charIndex * charIntCount + currentInt] >> currentIntBitPosition) & 1;

src/org/warp/picalculator/gui/DisplayManager.java

@@ -1,10 +1,6 @@
 package org.warp.picalculator.gui;
 
 import java.io.IOException;
-import java.lang.management.ManagementFactory;
-import java.lang.management.OperatingSystemMXBean;
-import java.lang.reflect.Method;
-import java.lang.reflect.Modifier;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 import org.warp.picalculator.Main;
@@ -373,7 +369,7 @@ public final class DisplayManager implements RenderingLoop {
 			}
 
 			//Working thread
-			Thread workThread = new Thread(() -> {
+			final Thread workThread = new Thread(() -> {
 				try {
 					while (true) {
 						float dt = 0;

src/org/warp/picalculator/gui/GUIErrorMessage.java

@@ -6,25 +6,25 @@ import org.warp.picalculator.Error;
 
 public class GUIErrorMessage {
 
-	private String err;
+	private final String err;
-	private long creationTime;
+	private final long creationTime;
 
 	public GUIErrorMessage(Error e) {
-		this.err = e.getLocalizedMessage();
+		err = e.getLocalizedMessage();
-		this.creationTime = System.currentTimeMillis();
+		creationTime = System.currentTimeMillis();
 	}
 
 	public GUIErrorMessage(Exception ex) {
 		err = ex.getLocalizedMessage();
-		this.creationTime = System.currentTimeMillis();
+		creationTime = System.currentTimeMillis();
 	}
 
 	public void draw(GraphicEngine g, Renderer r, String msg) {
-		int scrW = g.getWidth();
+		final int scrW = g.getWidth();
-		int scrH = g.getHeight();
+		final int scrH = g.getHeight();
-		int width = 200;
+		final int width = 200;
-		int height = 20;
+		final int height = 20;
-		int margin = 4;
+		final int margin = 4;
 		r.glClearSkin();
 		r.glColor(0x00000000);
 		r.glFillRect(scrW - width - margin, scrH - height - margin, width, height, 0, 0, 0, 0);

src/org/warp/picalculator/gui/GraphicUtils.java

@@ -1,23 +1,19 @@
 package org.warp.picalculator.gui;
 
 public class GraphicUtils {
-	   public static final float sin(float rad)
+	public static final float sin(float rad) {
-	   {
 		return sin[(int) (rad * radToIndex) & SIN_MASK];
 	}
 
-	   public static final float cos(float rad)
+	public static final float cos(float rad) {
-	   {
 		return cos[(int) (rad * radToIndex) & SIN_MASK];
 	}
 
-	   public static final float sinDeg(float deg)
+	public static final float sinDeg(float deg) {
-	   {
 		return sin[(int) (deg * degToIndex) & SIN_MASK];
 	}
 
-	   public static final float cosDeg(float deg)
+	public static final float cosDeg(float deg) {
-	   {
 		return cos[(int) (deg * degToIndex) & SIN_MASK];
 	}
 
@@ -27,8 +23,7 @@ public class GraphicUtils {
 	private static final float degFull, degToIndex;
 	private static final float[] sin, cos;
 
-	   static
+	static {
-	   {
 		RAD = (float) Math.PI / 180.0f;
 		DEG = 180.0f / (float) Math.PI;
 
@@ -44,15 +39,13 @@ public class GraphicUtils {
 		sin = new float[SIN_COUNT];
 		cos = new float[SIN_COUNT];
 
-	      for (int i = 0; i < SIN_COUNT; i++)
+		for (int i = 0; i < SIN_COUNT; i++) {
-	      {
 			sin[i] = (float) Math.sin((i + 0.5f) / SIN_COUNT * radFull);
 			cos[i] = (float) Math.cos((i + 0.5f) / SIN_COUNT * radFull);
 		}
 
 		// Four cardinal directions (credits: Nate)
-	      for (int i = 0; i < 360; i += 90)
+		for (int i = 0; i < 360; i += 90) {
-	      {
 			sin[(int) (i * degToIndex) & SIN_MASK] = (float) Math.sin(i * Math.PI / 180.0);
 			cos[(int) (i * degToIndex) & SIN_MASK] = (float) Math.cos(i * Math.PI / 180.0);
 		}

src/org/warp/picalculator/gui/GraphicalElement.java

@@ -3,7 +3,9 @@ package org.warp.picalculator.gui;
 public interface GraphicalElement {
 
 	/**
-	 * Recompute element's dimension parameters, like <strong>width</strong>, <strong>height</strong>, <strong>line</strong> or <strong>length</strong>.
+	 * Recompute element's dimension parameters, like <strong>width</strong>,
+	 * <strong>height</strong>, <strong>line</strong> or
+	 * <strong>length</strong>.
 	 */
 	public void recomputeDimensions();
 
@@ -21,7 +23,8 @@ public interface GraphicalElement {
 
 	/**
 	 * 
-	 * @return Position of the vertical alignment line of the element, relative to itself.
+	 * @return Position of the vertical alignment line of the element, relative
+	 *         to itself.
 	 */
 	public int getLine();
 }

src/org/warp/picalculator/gui/expression/Block.java

@@ -3,7 +3,6 @@ package org.warp.picalculator.gui.expression;
 import org.warp.picalculator.gui.GraphicalElement;
 import org.warp.picalculator.gui.graphicengine.GraphicEngine;
 import org.warp.picalculator.gui.graphicengine.Renderer;
-import org.warp.picalculator.math.parser.features.interfaces.Feature;
 
 public abstract class Block implements GraphicalElement {
 
@@ -14,9 +13,12 @@ public abstract class Block implements GraphicalElement {
 
 	/**
 	 * 
-	 * @param r Graphic Renderer class.
+	 * @param r
-	 * @param x Position relative to the window.
+	 *            Graphic Renderer class.
-	 * @param y Position relative to the window.
+	 * @param x
+	 *            Position relative to the window.
+	 * @param y
+	 *            Position relative to the window.
 	 * @param small
 	 */
 	public abstract void draw(GraphicEngine ge, Renderer r, int x, int y, Caret caret);

src/org/warp/picalculator/gui/expression/BlockChar.java

@@ -2,8 +2,6 @@ package org.warp.picalculator.gui.expression;
 
 import org.warp.picalculator.gui.graphicengine.GraphicEngine;
 import org.warp.picalculator.gui.graphicengine.Renderer;
-import org.warp.picalculator.math.parser.features.FeatureChar;
-import org.warp.picalculator.math.parser.features.interfaces.Feature;
 
 public class BlockChar extends Block {
 

src/org/warp/picalculator/gui/expression/BlockContainer.java

@@ -41,7 +41,7 @@ public class BlockContainer implements GraphicalElement {
 		this.minWidth = minWidth;
 		this.minHeight = minHeight;
 		this.withBorder = withBorder;
-		for (Block b: content) {
+		for (final Block b : content) {
 			if (b.isSmall() != small) {
 				b.setSmall(small);
 			}
@@ -63,11 +63,15 @@ public class BlockContainer implements GraphicalElement {
 	}
 
 	public void appendBlock(Block b) {
+		appendBlockUnsafe(b);
+		recomputeDimensions();
+	}
+
+	public void appendBlockUnsafe(Block b) {
 		if (b.isSmall() != small) {
 			b.setSmall(small);
 		}
 		content.add(b);
-		recomputeDimensions();
 	}
 
 	public void removeBlock(Block b) {
@@ -91,11 +95,16 @@ public class BlockContainer implements GraphicalElement {
 
 	/**
 	 * 
-	 * @param ge Graphic Engine class.
+	 * @param ge
-	 * @param r Graphic Renderer class of <b>ge</b>.
+	 *            Graphic Engine class.
-	 * @param x Position relative to the window.
+	 * @param r
-	 * @param y Position relative to the window.
+	 *            Graphic Renderer class of <b>ge</b>.
-	 * @param caret Position of the caret.
+	 * @param x
+	 *            Position relative to the window.
+	 * @param y
+	 *            Position relative to the window.
+	 * @param caret
+	 *            Position of the caret.
 	 */
 	public void draw(GraphicEngine ge, Renderer r, int x, int y, Caret caret) {
 		int paddingX = 1;
@@ -114,11 +123,13 @@ public class BlockContainer implements GraphicalElement {
 			r.glDrawLine(x + paddingX + width - 1, y, x + paddingX + width - 1, y + height - 1);
 			r.glDrawLine(x + paddingX, y + height - 1, x + paddingX + width - 1, y + height - 1);
 		} else {
-			for (Block b : content) {
+			for (final Block b : content) {
 				caret.skip(1);
 				b.draw(ge, r, x + paddingX, y + line - b.line, caret);
 				paddingX += b.getWidth();
-				if (caret.getRemaining() == 0) BlockContainer.drawCaret(ge, r, caret, x + paddingX, y+line-b.line, b.height);
+				if (caret.getRemaining() == 0) {
+					BlockContainer.drawCaret(ge, r, caret, x + paddingX, y + line - b.line, b.height);
+				}
 				paddingX += 1;
 			}
 		}
@@ -129,17 +140,17 @@ public class BlockContainer implements GraphicalElement {
 		boolean added = false;
 
 		if (caret.getRemaining() == 0) {
-			this.addBlock(0, newBlock);
+			addBlock(0, newBlock);
 			added = true;
 		}
 
 		int pos = 0;
-		for (Block b : content) {
+		for (final Block b : content) {
 			caret.skip(1);
 			pos++;
 			added = added | b.putBlock(caret, newBlock);
 			if (caret.getRemaining() == 0) {
-				this.addBlock(pos, newBlock);
+				addBlock(pos, newBlock);
 				added = true;
 			}
 		}
@@ -154,13 +165,13 @@ public class BlockContainer implements GraphicalElement {
 		boolean removed = false;
 
 		int pos = 0;
-		for (Block b : content) {
+		for (final Block b : content) {
 			caret.skip(1);
 			pos++;
-			int deltaCaret = caret.getRemaining();
+			final int deltaCaret = caret.getRemaining();
 			removed = removed | b.delBlock(caret);
 			if (caret.getRemaining() == 0 || (removed == false && deltaCaret >= 0 && caret.getRemaining() < 0)) {
-				this.removeAt(pos-1);
+				removeAt(pos - 1);
 				caret.setPosition(caret.getPosition() - deltaCaret);
 				removed = true;
 			}
@@ -172,7 +183,6 @@ public class BlockContainer implements GraphicalElement {
 		return removed;
 	}
 
-
 	@Override
 	public void recomputeDimensions() {
 		int l = 0; //Line
@@ -180,7 +190,7 @@ public class BlockContainer implements GraphicalElement {
 		int h2 = 0; //Height under the line. h = h2 + l
 		int h = 0; //Height
 
-		for (Block b : content) {
+		for (final Block b : content) {
 			w += b.getWidth() + 1;
 			final int bl = b.getLine();
 			final int bh = b.getHeight();
@@ -280,12 +290,14 @@ public class BlockContainer implements GraphicalElement {
 	}
 
 	private static void checkInitialized() {
-		if (!initialized) throw new ExceptionInInitializerError("Please initialize BlockContainer by running the method BlockContainer.initialize(...) first!");
+		if (!initialized) {
+			throw new ExceptionInInitializerError("Please initialize BlockContainer by running the method BlockContainer.initialize(...) first!");
+		}
 	}
 
 	public int computeCaretMaxBound() {
 		int maxpos = 0;
-		for (Block b : content) {
+		for (final Block b : content) {
 			maxpos += 1 + b.computeCaretMaxBound();
 		}
 		return maxpos + 1;

src/org/warp/picalculator/gui/expression/BlockDivision.java

@@ -1,11 +1,7 @@
 package org.warp.picalculator.gui.expression;
 
-import org.warp.picalculator.Main;
 import org.warp.picalculator.gui.graphicengine.GraphicEngine;
 import org.warp.picalculator.gui.graphicengine.Renderer;
-import org.warp.picalculator.math.parser.features.interfaces.Feature;
-
-import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 public class BlockDivision extends Block {
 
@@ -19,8 +15,8 @@ public class BlockDivision extends Block {
 	private int h1;
 
 	public BlockDivision() {
-		this.containerUp = new BlockContainer(false);
+		containerUp = new BlockContainer(false);
-		this.containerDown = new BlockContainer(false);
+		containerDown = new BlockContainer(false);
 		recomputeDimensions();
 	}
 
@@ -82,8 +78,8 @@ public class BlockDivision extends Block {
 	@Override
 	public void setSmall(boolean small) {
 		this.small = small;
-		this.containerUp.setSmall(small);
+		containerUp.setSmall(small);
-		this.containerDown.setSmall(small);
+		containerDown.setSmall(small);
 		recomputeDimensions();
 	}
 

src/org/warp/picalculator/gui/expression/BlockParenthesis.java

@@ -10,7 +10,7 @@ public class BlockParenthesis extends Block {
 	private final BlockContainer containerNumber;
 
 	public BlockParenthesis() {
-		this.containerNumber = new BlockContainer(false);
+		containerNumber = new BlockContainer(false);
 		recomputeDimensions();
 	}
 
@@ -43,15 +43,15 @@ public class BlockParenthesis extends Block {
 
 	@Override
 	public void recomputeDimensions() {
-		this.width = containerNumber.getWidth()+BlockContainer.getDefaultCharWidth(small)*2;
+		width = containerNumber.getWidth() + BlockContainer.getDefaultCharWidth(small) * 2;
-		this.height = containerNumber.getHeight();
+		height = containerNumber.getHeight();
-		this.line = containerNumber.getLine();
+		line = containerNumber.getLine();
 	}
 
 	@Override
 	public void setSmall(boolean small) {
 		this.small = small;
-		this.containerNumber.setSmall(small);
+		containerNumber.setSmall(small);
 		recomputeDimensions();
 	}
 

src/org/warp/picalculator/gui/expression/BlockSquareRoot.java

@@ -1,11 +1,7 @@
 package org.warp.picalculator.gui.expression;
 
-import org.warp.picalculator.Main;
 import org.warp.picalculator.gui.graphicengine.GraphicEngine;
 import org.warp.picalculator.gui.graphicengine.Renderer;
-import org.warp.picalculator.math.parser.features.interfaces.Feature;
-
-import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 public class BlockSquareRoot extends Block {
 
@@ -16,7 +12,7 @@ public class BlockSquareRoot extends Block {
 	private int h1;
 
 	public BlockSquareRoot() {
-		this.containerNumber = new BlockContainer(false);
+		containerNumber = new BlockContainer(false);
 		recomputeDimensions();
 	}
 
@@ -72,7 +68,7 @@ public class BlockSquareRoot extends Block {
 	@Override
 	public void setSmall(boolean small) {
 		this.small = small;
-		this.containerNumber.setSmall(small);
+		containerNumber.setSmall(small);
 		recomputeDimensions();
 	}
 

src/org/warp/picalculator/gui/expression/Caret.java

@@ -9,7 +9,7 @@ public class Caret {
 	public Caret(CaretState state, int pos) {
 		this.state = state;
 		this.pos = pos;
-		this.remaining = pos;
+		remaining = pos;
 	}
 
 	public void skip(int i) {
@@ -29,21 +29,21 @@ public class Caret {
 	}
 
 	public void flipState() {
-		if (this.state == CaretState.VISIBLE_ON) {
+		if (state == CaretState.VISIBLE_ON) {
-			this.state = CaretState.VISIBLE_OFF;
+			state = CaretState.VISIBLE_OFF;
-		} else if (this.state == CaretState.VISIBLE_OFF) {
+		} else if (state == CaretState.VISIBLE_OFF) {
-			this.state = CaretState.VISIBLE_ON;
+			state = CaretState.VISIBLE_ON;
 		}
 	}
 
 	public void turnOn() {
-		if (this.state == CaretState.VISIBLE_OFF) {
+		if (state == CaretState.VISIBLE_OFF) {
-			this.state = CaretState.VISIBLE_ON;
+			state = CaretState.VISIBLE_ON;
 		}
 	}
 
 	public void setPosition(int i) {
-		this.pos = i;
+		pos = i;
 	}
 
 	public void resetRemaining() {

src/org/warp/picalculator/gui/expression/CaretState.java

@@ -1,7 +1,5 @@
 package org.warp.picalculator.gui.expression;
 
 public enum CaretState {
-	VISIBLE_ON,
+	VISIBLE_ON, VISIBLE_OFF, HIDDEN
-	VISIBLE_OFF,
-	HIDDEN
 }

src/org/warp/picalculator/gui/expression/containers/InputContainer.java

@@ -1,5 +1,8 @@
 package org.warp.picalculator.gui.expression.containers;
 
+import java.io.ObjectOutputStream;
+import java.io.Serializable;
+
 import org.warp.picalculator.gui.GraphicalElement;
 import org.warp.picalculator.gui.expression.Block;
 import org.warp.picalculator.gui.expression.BlockContainer;
@@ -9,12 +12,17 @@ import org.warp.picalculator.gui.expression.layouts.InputLayout;
 import org.warp.picalculator.gui.graphicengine.GraphicEngine;
 import org.warp.picalculator.gui.graphicengine.Renderer;
 
-public abstract class InputContainer implements GraphicalElement, InputLayout {
+import it.unimi.dsi.fastutil.Arrays;
-	public final BlockContainer root;
+import it.unimi.dsi.fastutil.objects.ObjectArrayList;
+
+public abstract class InputContainer implements GraphicalElement, InputLayout, Serializable {
+	private static final long serialVersionUID = 923589369317765667L;
+	private final BlockContainer root;
 	private Caret caret;
 	private static final float CARET_DURATION = 0.5f;
 	private float caretTime;
 	private int maxPosition = 0;
+	private boolean parsed = false;
 
 	public InputContainer() {
 		caret = new Caret(CaretState.VISIBLE_ON, 0);
@@ -32,7 +40,7 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 	}
 
 	public void typeChar(char c) {
-		Block b = parseChar(c);
+		final Block b = parseChar(c);
 		if (b != null) {
 			caret.resetRemaining();
 			if (root.putBlock(caret, b)) {
@@ -63,7 +71,7 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 	}
 
 	public void moveLeft() {
-		int curPos = caret.getPosition();
+		final int curPos = caret.getPosition();
 		if (curPos > 0) {
 			caret.setPosition(curPos - 1);
 		}
@@ -72,7 +80,7 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 	}
 
 	public void moveRight() {
-		int curPos = caret.getPosition();
+		final int curPos = caret.getPosition();
 		if (curPos + 1 < maxPosition) {
 			caret.setPosition(curPos + 1);
 		}
@@ -102,7 +110,8 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 
 	/**
 	 * 
-	 * @param delta Time, in seconds
+	 * @param delta
+	 *            Time, in seconds
 	 * @return true if something changed
 	 */
 	public boolean beforeRender(float delta) {
@@ -121,10 +130,14 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 
 	/**
 	 * 
-	 * @param ge Graphic Engine class.
+	 * @param ge
-	 * @param r Graphic Renderer class of <b>ge</b>.
+	 *            Graphic Engine class.
-	 * @param x Position relative to the window.
+	 * @param r
-	 * @param y Position relative to the window.
+	 *            Graphic Renderer class of <b>ge</b>.
+	 * @param x
+	 *            Position relative to the window.
+	 * @param y
+	 *            Position relative to the window.
 	 */
 	public void draw(GraphicEngine ge, Renderer r, int x, int y) {
 		caret.resetRemaining();
@@ -137,4 +150,37 @@ public abstract class InputContainer implements GraphicalElement, InputLayout {
 		maxPosition = root.computeCaretMaxBound();
 		recomputeDimensions();
 	}
+
+	public boolean isEmpty() {
+		return maxPosition <= 1;
+	}
+
+	public int getCaretMaxPosition() {
+		return maxPosition;
+	}
+
+	public void setCaretPosition(int pos) {
+		if (pos > 0 && pos < maxPosition) {
+			caret.setPosition(pos);
+		}
+		caret.turnOn();
+		caretTime = 0;
+	}
+
+	public void setParsed(boolean parsed) {
+		this.parsed = parsed;
+	}
+
+	public boolean isAlreadyParsed() {
+		return parsed;
+	}
+
+	/**
+	 * <strong>WARNING! DO NOT MODIFY THIS ARRAY!!!</strong>
+	 * 
+	 * @return an arraylist representing the content
+	 */
+	public ObjectArrayList<Block> getContent() {
+		return root.getContent();
+	}
 }

src/org/warp/picalculator/gui/expression/containers/NormalInputContainer.java

@@ -2,12 +2,9 @@ package org.warp.picalculator.gui.expression.containers;
 
 import org.warp.picalculator.gui.expression.Block;
 import org.warp.picalculator.gui.expression.BlockChar;
-import org.warp.picalculator.gui.expression.BlockContainer;
 import org.warp.picalculator.gui.expression.BlockDivision;
 import org.warp.picalculator.gui.expression.BlockParenthesis;
 import org.warp.picalculator.gui.expression.BlockSquareRoot;
-import org.warp.picalculator.gui.expression.Caret;
-import org.warp.picalculator.gui.expression.CaretState;
 import org.warp.picalculator.math.MathematicalSymbols;
 
 public class NormalInputContainer extends InputContainer {

src/org/warp/picalculator/gui/expression/containers/OutputContainer.java

@@ -1,15 +1,19 @@
 package org.warp.picalculator.gui.expression.containers;
 
+import java.io.Serializable;
+
 import org.warp.picalculator.gui.GraphicalElement;
 import org.warp.picalculator.gui.expression.Block;
 import org.warp.picalculator.gui.expression.BlockContainer;
 import org.warp.picalculator.gui.expression.Caret;
 import org.warp.picalculator.gui.expression.CaretState;
-import org.warp.picalculator.gui.expression.layouts.InputLayout;
 import org.warp.picalculator.gui.graphicengine.GraphicEngine;
 import org.warp.picalculator.gui.graphicengine.Renderer;
 
-public abstract class OutputContainer implements GraphicalElement, OutputLayout {
+import it.unimi.dsi.fastutil.objects.ObjectArrayList;
+
+public abstract class OutputContainer implements GraphicalElement, OutputLayout, Serializable {
+	private static final long serialVersionUID = -5714825964892683571L;
 	public final BlockContainer root;
 	private final Caret caret = new Caret(CaretState.HIDDEN, 0);
 
@@ -25,6 +29,14 @@ public abstract class OutputContainer implements GraphicalElement, OutputLayout
 		root = new BlockContainer(small);
 	}
 	
+	public void setContent(ObjectArrayList<Block> blocks) {
+		root.clear();
+		for (Block b : blocks) {
+			root.appendBlockUnsafe(b);
+		}
+		recomputeDimensions();
+	}
+
 	@Override
 	public void recomputeDimensions() {
 		root.recomputeDimensions();
@@ -47,7 +59,8 @@ public abstract class OutputContainer implements GraphicalElement, OutputLayout
 
 	/**
 	 * 
-	 * @param delta Time, in seconds
+	 * @param delta
+	 *            Time, in seconds
 	 */
 	public void beforeRender(double delta) {
 
@@ -55,10 +68,14 @@ public abstract class OutputContainer implements GraphicalElement, OutputLayout
 
 	/**
 	 * 
-	 * @param ge Graphic Engine class.
+	 * @param ge
-	 * @param r Graphic Renderer class of <b>ge</b>.
+	 *            Graphic Engine class.
-	 * @param x Position relative to the window.
+	 * @param r
-	 * @param y Position relative to the window.
+	 *            Graphic Renderer class of <b>ge</b>.
+	 * @param x
+	 *            Position relative to the window.
+	 * @param y
+	 *            Position relative to the window.
 	 */
 	public void draw(GraphicEngine ge, Renderer r, int x, int y) {
 		root.draw(ge, r, x, y, caret);

src/org/warp/picalculator/gui/graphicengine/Renderer.java

@@ -1,7 +1,5 @@
 package org.warp.picalculator.gui.graphicengine;
 
-import java.awt.FontMetrics;
-
 public interface Renderer {
 	public void glColor3i(int r, int gg, int b);
 
@@ -25,7 +23,8 @@ public interface Renderer {
 
 	public void glDrawLine(float x0, float y0, float x1, float y1);
 
-	public void glFillRect(float x, float y, float width, float height, float uvX, float uvY, float uvWidth, float uvHeight);
+	public void glFillRect(float x, float y, float width, float height, float uvX, float uvY, float uvWidth,
+			float uvHeight);
 
 	public void glFillColor(float x, float y, float width, float height);
 

src/org/warp/picalculator/gui/graphicengine/cpu/CPUEngine.java

@@ -87,7 +87,7 @@ public class CPUEngine implements GraphicEngine {
 	@Override
 	public void start(RenderingLoop d) {
 		INSTANCE.setRenderingLoop(d);
-		Thread th = new Thread(() -> {
+		final Thread th = new Thread(() -> {
 			try {
 				double extratime = 0;
 				while (initialized) {
@@ -464,7 +464,7 @@ public class CPUEngine implements GraphicEngine {
 			do {
 				Thread.sleep(500);
 			} while (initialized);
-		} catch (InterruptedException e) {
+		} catch (final InterruptedException e) {
 
 		}
 	}

src/org/warp/picalculator/gui/graphicengine/cpu/CPUSkin.java

@@ -5,7 +5,6 @@ import java.io.IOException;
 
 import javax.imageio.ImageIO;
 
-import org.warp.picalculator.Main;
 import org.warp.picalculator.gui.graphicengine.GraphicEngine;
 import org.warp.picalculator.gui.graphicengine.Skin;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUEngine.CPURenderer;

src/org/warp/picalculator/gui/graphicengine/gpu/GPUEngine.java

@@ -9,7 +9,6 @@ import org.warp.picalculator.gui.graphicengine.BinaryFont;
 import org.warp.picalculator.gui.graphicengine.Skin;
 
 import com.jogamp.opengl.GLProfile;
-import com.jogamp.opengl.egl.EGL;
 
 public class GPUEngine implements org.warp.picalculator.gui.graphicengine.GraphicEngine {
 
@@ -47,8 +46,8 @@ public class GPUEngine implements org.warp.picalculator.gui.graphicengine.Graphi
 
 	@Override
 	public void setDisplayMode(int ww, int wh) {
-		this.size[0] = ww;
+		size[0] = ww;
-		this.size[1] = wh;
+		size[1] = wh;
 		wnd.window.setSize(Utils.debugOn ? ww * 2 : ww, Utils.debugOn ? wh * 2 : wh);
 	}
 
@@ -93,7 +92,7 @@ public class GPUEngine implements org.warp.picalculator.gui.graphicengine.Graphi
 
 	@Override
 	public void repaint() {
-		if (d != null & r != null && r.gl != null) {
+		if (d != null & r != null && GPURenderer.gl != null) {
 			d.refresh();
 		}
 	}
@@ -119,14 +118,14 @@ public class GPUEngine implements org.warp.picalculator.gui.graphicengine.Graphi
 			do {
 				Thread.sleep(500);
 			} while (initialized | created);
-		} catch (InterruptedException e) {
+		} catch (final InterruptedException e) {
 
 		}
 	}
 
 	@Override
 	public boolean isSupported() {
-		boolean available = GLProfile.isAvailable(GLProfile.GL2ES1);
+		final boolean available = GLProfile.isAvailable(GLProfile.GL2ES1);
 		if (!available) {
 			System.err.println(GLProfile.glAvailabilityToString());
 		}

src/org/warp/picalculator/gui/graphicengine/gpu/GPUFont.java

@@ -1,11 +1,8 @@
 package org.warp.picalculator.gui.graphicengine.gpu;
 
 import java.awt.image.BufferedImage;
-import java.io.File;
 import java.io.IOException;
 
-import javax.imageio.ImageIO;
-
 import org.warp.picalculator.gui.graphicengine.GraphicEngine;
 import org.warp.picalculator.gui.graphicengine.BinaryFont;
 import org.warp.picalculator.gui.graphicengine.cpu.CPUFont;

src/org/warp/picalculator/gui/graphicengine/gpu/GPURenderer.java

@@ -1,6 +1,5 @@
 package org.warp.picalculator.gui.graphicengine.gpu;
 
-import java.awt.FontMetrics;
 import java.awt.image.BufferedImage;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
@@ -43,9 +42,9 @@ public class GPURenderer implements Renderer {
 
 	@Override
 	public void glColor3i(int r, int gg, int b) {
-		final float red = ((float)r) / 255f;
+		final float red = (r) / 255f;
-		final float gre = ((float)gg) / 255f;
+		final float gre = (gg) / 255f;
-		final float blu = ((float)b) / 255f;
+		final float blu = (b) / 255f;
 		currentColor = new float[] { red, gre, blu, 1.0f, red, gre, blu, 1.0f, red, gre, blu, 1.0f, red, gre, blu, 1.0f, };
 	}
 
@@ -75,10 +74,10 @@ public class GPURenderer implements Renderer {
 
 	@Override
 	public void glClearColor(int rgb) {
-		final float alpha = (float)((rgb >> 24) & 0xFF) / 255f;
+		final float alpha = ((rgb >> 24) & 0xFF) / 255f;
-		final float red = (float)((rgb >> 16) & 0xFF) / 255f;
+		final float red = ((rgb >> 16) & 0xFF) / 255f;
-		final float green = (float)((rgb >> 8) & 0xFF) / 255f;
+		final float green = ((rgb >> 8) & 0xFF) / 255f;
-		final float blue = (float)(rgb & 0xFF) / 255f;
+		final float blue = (rgb & 0xFF) / 255f;
 		glClearColor4f(red, green, blue, alpha);
 	}
 
@@ -117,7 +116,8 @@ public class GPURenderer implements Renderer {
 	}
 
 	@Override
-	public void glFillRect(float x, float y, float width, float height, float uvX, float uvY, float uvWidth, float uvHeight) {
+	public void glFillRect(float x, float y, float width, float height, float uvX, float uvY, float uvWidth,
+			float uvHeight) {
 		enableTexture();
 		uvWidth /= currentTexWidth;
 		uvX /= currentTexWidth;
@@ -145,7 +145,7 @@ public class GPURenderer implements Renderer {
 	@Override
 	public void glDrawStringLeft(float x, float y, String text) {
 		final int txtLen = text.length();
-		int[] txtArray = currentFont.getCharIndexes(text);
+		final int[] txtArray = currentFont.getCharIndexes(text);
 		int tableIndexX;
 		int tableIndexY;
 		for (int currentCharIndex = 0; currentCharIndex < txtLen; currentCharIndex++) {
@@ -167,9 +167,9 @@ public class GPURenderer implements Renderer {
 
 	@Override
 	public void glDrawCharLeft(int x, int y, char ch) {
-		int index = currentFont.getCharIndex(ch);
+		final int index = currentFont.getCharIndex(ch);
-		int tableIndexX = index % currentFont.memoryWidthOfEachColumn;
+		final int tableIndexX = index % currentFont.memoryWidthOfEachColumn;
-		int tableIndexY = (index - tableIndexX) / currentFont.memoryWidthOfEachColumn;
+		final int tableIndexY = (index - tableIndexX) / currentFont.memoryWidthOfEachColumn;
 		glFillRect(x, y, currentFont.charW, currentFont.charH, tableIndexX * currentFont.charW, tableIndexY * currentFont.charH, currentFont.charW, currentFont.charH);
 	}
 
@@ -208,7 +208,7 @@ public class GPURenderer implements Renderer {
 		final ByteArrayOutputStream os = new ByteArrayOutputStream();
 		ImageIO.write(img, "png", os);
 		final InputStream fis = new ByteArrayInputStream(os.toByteArray());
-		Texture tex = TextureIO.newTexture(fis, false, TextureIO.PNG);
+		final Texture tex = TextureIO.newTexture(fis, false, TextureIO.PNG);
 		tex.setTexParameteri(gl, GL.GL_TEXTURE_MIN_FILTER, GL.GL_NEAREST);
 		tex.setTexParameteri(gl, GL.GL_TEXTURE_MAG_FILTER, GL.GL_NEAREST);
 		return tex;
@@ -248,10 +248,10 @@ public class GPURenderer implements Renderer {
 			precTexEnabled = currentTexEnabled;
 			precTex = currentTex;
 			if (currentTexEnabled) {
-				gl.glEnable(GL2ES1.GL_TEXTURE_2D);
+				gl.glEnable(GL.GL_TEXTURE_2D);
 				currentTex.bind(gl);
 			} else {
-				gl.glDisable(GL2ES1.GL_TEXTURE_2D);
+				gl.glDisable(GL.GL_TEXTURE_2D);
 			}
 		}
 

src/org/warp/picalculator/gui/graphicengine/gpu/GPUSkin.java

@@ -5,6 +5,7 @@ import java.io.IOException;
 import org.warp.picalculator.gui.graphicengine.GraphicEngine;
 import org.warp.picalculator.gui.graphicengine.Skin;
 
+import com.jogamp.opengl.GL;
 import com.jogamp.opengl.GL2ES1;
 import com.jogamp.opengl.GLException;
 import com.jogamp.opengl.util.texture.Texture;
@@ -33,12 +34,12 @@ public class GPUSkin implements Skin {
 	@Override
 	public void initialize(GraphicEngine d) {
 		try {
-			BufferedImage i = GPURenderer.openTexture(texturePath);
+			final BufferedImage i = GPURenderer.openTexture(texturePath);
-			GL2ES1 gl = ((GPURenderer)d.getRenderer()).gl;
+			final GL2ES1 gl = GPURenderer.gl;
 			t = GPURenderer.importTexture(i);
 			w = i.getWidth();
 			h = i.getHeight();
-			t.setTexParameteri(gl, GL2ES1.GL_TEXTURE_MAG_FILTER, GL2ES1.GL_NEAREST);
+			t.setTexParameteri(gl, GL.GL_TEXTURE_MAG_FILTER, GL.GL_NEAREST);
 			initialized = true;
 		} catch (GLException | IOException e) {
 			e.printStackTrace();

src/org/warp/picalculator/gui/graphicengine/gpu/NEWTWindow.java

@@ -33,13 +33,10 @@ import com.jogamp.opengl.GL2ES1;
 import com.jogamp.opengl.GLAutoDrawable;
 import com.jogamp.opengl.GLEventListener;
 import com.jogamp.opengl.GLProfile;
+import com.jogamp.opengl.fixedfunc.GLLightingFunc;
 import com.jogamp.opengl.fixedfunc.GLMatrixFunc;
 import com.jogamp.opengl.fixedfunc.GLPointerFunc;
 import com.jogamp.opengl.GLCapabilities;
-import com.jogamp.nativewindow.util.DimensionImmutable;
-import com.jogamp.nativewindow.util.PixelFormat;
-import com.jogamp.nativewindow.util.PixelRectangle;
-import com.jogamp.newt.NewtFactory;
 import com.jogamp.newt.event.KeyEvent;
 import com.jogamp.newt.event.KeyListener;
 import com.jogamp.newt.event.WindowEvent;
@@ -49,16 +46,10 @@ import com.jogamp.newt.opengl.GLWindow;
 
 import com.jogamp.opengl.util.*;
 
-import java.awt.event.ComponentEvent;
-import java.awt.event.ComponentListener;
-import java.nio.ByteBuffer;
-import java.util.Collection;
-
 import org.warp.picalculator.Utils;
 import org.warp.picalculator.device.Keyboard;
 import org.warp.picalculator.device.Keyboard.Key;
 import org.warp.picalculator.gui.DisplayManager;
-import org.warp.picalculator.gui.graphicengine.GraphicEngine;
 
 /**
  *
@@ -277,9 +268,9 @@ class NEWTWindow implements GLEventListener {
 		gl.glEnable(GL.GL_TEXTURE_2D);
 
 		//Transparency
-		gl.glEnable(GL2ES1.GL_BLEND);
+		gl.glEnable(GL.GL_BLEND);
-		gl.glBlendFunc(GL2ES1.GL_SRC_ALPHA, GL2ES1.GL_ONE_MINUS_SRC_ALPHA);
+		gl.glBlendFunc(GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA);
-		gl.glShadeModel(GL2ES1.GL_FLAT);
+		gl.glShadeModel(GLLightingFunc.GL_FLAT);
 
 		try {
 			renderer.currentTex = ((GPUSkin) disp.loadSkin("test.png")).t;
@@ -329,7 +320,7 @@ class NEWTWindow implements GLEventListener {
 	public void display(GLAutoDrawable glad) {
 		final GL2ES1 gl = glad.getGL().getGL2ES1();
 
-		renderer.gl = gl;
+		GPURenderer.gl = gl;
 
 		gl.glEnableClientState(GLPointerFunc.GL_COLOR_ARRAY);
 		gl.glEnableClientState(GLPointerFunc.GL_VERTEX_ARRAY);
@@ -341,7 +332,7 @@ class NEWTWindow implements GLEventListener {
 
 		renderer.endDrawCycle();
 
-		renderer.gl = null;
+		GPURenderer.gl = null;
 
 		gl.glDisableClientState(GLPointerFunc.GL_COLOR_ARRAY);
 		gl.glDisableClientState(GLPointerFunc.GL_TEXTURE_COORD_ARRAY);

src/org/warp/picalculator/gui/screens/KeyboardDebugScreen.java

@@ -29,7 +29,7 @@ public class KeyboardDebugScreen extends Screen {
 
 	@Override
 	public void render() {
-		Renderer renderer = DisplayManager.renderer;
+		final Renderer renderer = DisplayManager.renderer;
 		fonts[2].use(DisplayManager.engine);
 		renderer.glColor4f(0.75f, 0.0f, 0.0f, 1.0f);
 		renderer.glDrawStringRight(Main.screenSize[0] - 10, 30, "-" + keyevent.toUpperCase() + "-");

src/org/warp/picalculator/gui/screens/LoadingScreen.java

@@ -1,8 +1,5 @@
 package org.warp.picalculator.gui.screens;
 
-import static org.warp.picalculator.gui.DisplayManager.colore;
-import static org.warp.picalculator.gui.DisplayManager.fonts;
-
 import org.warp.picalculator.Main;
 import org.warp.picalculator.device.Keyboard.Key;
 import org.warp.picalculator.gui.DisplayManager;

src/org/warp/picalculator/gui/screens/MarioScreen.java

@@ -1,11 +1,7 @@
 package org.warp.picalculator.gui.screens;
 
-import java.awt.image.BufferedImage;
 import java.io.IOException;
 
-import javax.imageio.ImageIO;
-
-import org.warp.picalculator.Main;
 import org.warp.picalculator.device.Keyboard;
 import org.warp.picalculator.device.Keyboard.Key;
 import org.warp.picalculator.gui.DisplayManager;
@@ -37,7 +33,7 @@ public class MarioScreen extends Screen {
 		try {
 			skin = DisplayManager.engine.loadSkin("marioskin.png");
 			groundskin = DisplayManager.engine.loadSkin("marioground.png");
-		} catch (IOException e) {
+		} catch (final IOException e) {
 			e.printStackTrace();
 		}
 	}

src/org/warp/picalculator/gui/screens/MathInputScreen.java

@@ -4,19 +4,20 @@ import java.io.IOException;
 import java.io.PrintWriter;
 import java.io.StringWriter;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
+import sun.reflect.generics.reflectiveObjects.NotImplementedException;
+
 import java.util.Collections;
-import java.util.Iterator;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Set;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Errors;
-import org.warp.picalculator.Main;
 import org.warp.picalculator.Utils;
 import org.warp.picalculator.device.Keyboard;
 import org.warp.picalculator.device.Keyboard.Key;
 import org.warp.picalculator.gui.DisplayManager;
+import org.warp.picalculator.gui.expression.Block;
 import org.warp.picalculator.gui.expression.BlockContainer;
 import org.warp.picalculator.gui.expression.containers.InputContainer;
 import org.warp.picalculator.gui.expression.containers.NormalInputContainer;
@@ -34,6 +35,8 @@ import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.functions.Variable;
 import org.warp.picalculator.math.functions.Variable.VariableValue;
 import org.warp.picalculator.math.functions.equations.Equation;
+import org.warp.picalculator.math.parser.MathParser;
+import org.warp.picalculator.math.functions.Expression;
 import org.warp.picalculator.math.functions.Number;
 
 public class MathInputScreen extends Screen {
@@ -55,7 +58,7 @@ public class MathInputScreen extends Screen {
 
 		try {
 			BlockContainer.initializeFonts(DisplayManager.engine.loadFont("ex"), DisplayManager.engine.loadFont("big"));
-		} catch (IOException e) {
+		} catch (final IOException e) {
 			e.printStackTrace();
 			System.exit(1);
 		}
@@ -88,7 +91,7 @@ public class MathInputScreen extends Screen {
 
 	@Override
 	public void renderStatusbar() {
-		Renderer renderer = DisplayManager.renderer;
+		final Renderer renderer = DisplayManager.renderer;
 		renderer.glColor3f(1, 1, 1);
 		final int pos = 2;
 		final int spacersNumb = 1;
@@ -111,7 +114,7 @@ public class MathInputScreen extends Screen {
 		userInput.draw(DisplayManager.engine, DisplayManager.renderer, padding, padding + 20);
 
 		if (!result.root.getContent().isEmpty()) {
-			result.draw(DisplayManager.engine, DisplayManager.renderer, DisplayManager.engine.getWidth() - 2, DisplayManager.engine.getHeight() - 2);
+			result.draw(DisplayManager.engine, DisplayManager.renderer, DisplayManager.engine.getWidth() - result.getWidth() - 2, DisplayManager.engine.getHeight() - result.getHeight() - 2);
 		}
 	}
 
@@ -127,6 +130,7 @@ public class MathInputScreen extends Screen {
 
 	@Override
 	public boolean keyPressed(Key k) {
+		Utils.debug.println(k.toString());
 		switch (k) {
 			case STEP:
 //				if (newExpression.length() > 0) {
@@ -160,46 +164,51 @@ public class MathInputScreen extends Screen {
 //				}
 //				return true;
 			case SIMPLIFY:
-//				if (DisplayManager.error != null) {
+				if (DisplayManager.error != null) {
-//					Utils.debug.println("Resetting after error...");
+					//TODO: make the error management a global API rather than being relegated to this screen.
-//					DisplayManager.error = null;
+					Utils.debug.println("Resetting after error...");
-//					currentExpression = null;
+					DisplayManager.error = null;
-//					calc.f = null;
+					calc.f = null;
-//					calc.f2 = null;
+					calc.f2 = null;
-//					calc.resultsCount = 0;
+					calc.resultsCount = 0;
-//					return true;
+					return true;
-//				} else {
+				} else {
-//					try {
+					try {
-//						try {
+						try {
-//							if (!firstStep) {
+							if (!userInput.isAlreadyParsed() && !userInput.isEmpty()) {
-//								step();
+								Expression expr = MathParser.parseInput(calc, userInput);
-//							} else {
+								if (calc.f == null | calc.f2 == null) {
-//								if (newExpression != currentExpression && newExpression.length() > 0) {
+									calc.f = new ObjectArrayList<>();
-//									changeEquationScreen();
+									calc.f2 = new ObjectArrayList<>();
-//									interpreta(true);
+								} else {
+									calc.f.clear();
+									calc.f2.clear();
+								}
+								calc.f.add(expr);
+								ObjectArrayList<Function> resultExpression = expr.solve();
+								ObjectArrayList<Block> resultBlocks = MathParser.parseOutput(calc, resultExpression);
+								result.setContent(resultBlocks);
 //								showVariablesDialog(() -> {
 //									currentExpression = newExpression;
 //									simplify();
 //								});
-//								}
+							}
-//							}
+						} catch (final Exception ex) {
-//						} catch (final Exception ex) {
+							if (Utils.debugOn) {
-//							if (Utils.debugOn) {
+								ex.printStackTrace();
-//								ex.printStackTrace();
+							}
-//							}
+							throw new Error(Errors.SYNTAX_ERROR);
-//							throw new Error(Errors.SYNTAX_ERROR);
+						}
-//						}
+					} catch (final Error e) {
-//					} catch (final Error e) {
+						final StringWriter sw = new StringWriter();
-//						final StringWriter sw = new StringWriter();
+						final PrintWriter pw = new PrintWriter(sw);
-//						final PrintWriter pw = new PrintWriter(sw);
+						e.printStackTrace(pw);
-//						e.printStackTrace(pw);
+						d.errorStackTrace = sw.toString().toUpperCase().replace("\t", "    ").replace("\r", "").split("\n");
-//						d.errorStackTrace = sw.toString().toUpperCase().replace("\t", "    ").replace("\r", "").split("\n");
+						DisplayManager.error = e.id.toString();
-//						DisplayManager.error = e.id.toString();
+						System.err.println(e.id);
-//						System.err.println(e.id);
+					}
-//					}
-//					return true;
-//				}
 					return true;
+				}
 			case NUM0:
 				typeChar('0');
 				return true;
@@ -317,13 +326,13 @@ public class MathInputScreen extends Screen {
 				}
 				return true;
 			case SURD_MODE:
-//				calc.exactMode = !calc.exactMode;
+				calc.exactMode = !calc.exactMode;
-//				if (calc.exactMode == false) {
+				if (calc.exactMode == false) {
-//					calc.f2 = solveExpression(calc.f2);
+					calc.f2 = solveExpression(calc.f2);
-//				} else {
+				} else {
-//					currentExpression = "";
+					result.clear();
-//					Keyboard.keyPressed(Key.SIMPLIFY);
+					Keyboard.keyPressed(Key.SIMPLIFY);
-//				}
+				}
 				return true;
 			case debug1:
 				DisplayManager.INSTANCE.setScreen(new EmptyScreen());
@@ -436,9 +445,6 @@ public class MathInputScreen extends Screen {
 					results.clear();
 					results.addAll(hs);
 					calc.f2 = results;
-					for (final Function rf : calc.f2) {
-						rf.recomputeDimensions(null);
-					}
 				}
 				Utils.debug.println(calc.f2.toString());
 			} catch (final Exception ex) {
@@ -479,9 +485,6 @@ public class MathInputScreen extends Screen {
 					results.clear();
 					results.addAll(hs);
 					calc.f2 = results;
-					for (final Function rf : calc.f2) {
-						rf.recomputeDimensions(null);
-					}
 				}
 			} catch (final Exception ex) {
 				if (Utils.debugOn) {
@@ -499,20 +502,19 @@ public class MathInputScreen extends Screen {
 		}
 	}
 
+	@SuppressWarnings("unused")
+	@Deprecated
 	private void changeEquationScreen() {
-		if (currentExpression != null && currentExpression.length() > 0) {
+		throw new NotImplementedException();
-			final MathInputScreen cloned = clone();
+//		
-			cloned.caretPos = cloned.currentExpression.length();
+//		if (!userInput.isEmpty()) {
-			cloned.newExpression = cloned.currentExpression;
+//			final MathInputScreen cloned = clone();
-			cloned.scrollX = fontBig.getStringWidth(cloned.currentExpression);
+//			cloned.userInput.setCaretPosition(cloned.userInput.getCaretMaxPosition()-1);
-			try {
+//			DisplayManager.INSTANCE.replaceScreen(cloned);
-				cloned.interpreta(true);
+//			initialized = false;
-			} catch (final Error e) {}
+//			DisplayManager.INSTANCE.setScreen(this);
-			DisplayManager.INSTANCE.replaceScreen(cloned);
+//
-			initialized = false;
+//		}
-			DisplayManager.INSTANCE.setScreen(this);
-
-		}
 	}
 
 	public void typeChar(char chr) {
@@ -594,15 +596,17 @@ public class MathInputScreen extends Screen {
 	}
 
 	@Override
+	@Deprecated
 	public MathInputScreen clone() {
-		final MathInputScreen es = this;
+		throw new NotImplementedException();
-		final MathInputScreen es2 = new MathInputScreen();
+//		final MathInputScreen es = this;
-		es2.errorLevel = es.errorLevel;
+//		final MathInputScreen es2 = new MathInputScreen();
-		es2.mustRefresh = es.mustRefresh;
+//		es2.errorLevel = es.errorLevel;
-		es2.calc = Utils.cloner.deepClone(es.calc);
+//		es2.mustRefresh = es.mustRefresh;
-		es2.userInput = Utils.cloner.deepClone(es.userInput);
+//		es2.calc = Utils.cloner.deepClone(es.calc);
-		es2.result = Utils.cloner.deepClone(es.result);
+//		es2.userInput = Utils.cloner.deepClone(es.userInput);
-		return es2;
+//		es2.result = Utils.cloner.deepClone(es.result);
+//		return es2;
 	}
 
 }

src/org/warp/picalculator/gui/screens/SolveEquationScreen.java

@@ -1,10 +1,8 @@
 package org.warp.picalculator.gui.screens;
 
-import org.warp.picalculator.Error;
 import org.warp.picalculator.Main;
 import org.warp.picalculator.device.Keyboard.Key;
 import org.warp.picalculator.gui.DisplayManager;
-import org.warp.picalculator.math.MathContext;
 
 public class SolveEquationScreen extends Screen {
 

src/org/warp/picalculator/math/Function.java

@@ -8,6 +8,7 @@ public interface Function {
 
 	/**
 	 * Returns this function and its children in a string form.
+	 * 
 	 * @return This function and its children in a string form.
 	 */
 	@Override
@@ -18,27 +19,34 @@ public interface Function {
 
 	/**
 	 * Deep clone this function.
+	 * 
 	 * @return A clone of this function.
 	 */
 	public Function clone();
 
 	/**
 	 * Generic method to change a parameter in a known position.
-	 * @param index parameter index.
+	 * 
-	 * @param var parameter.
+	 * @param index
+	 *            parameter index.
+	 * @param var
+	 *            parameter.
 	 * @return A new instance of this function.
 	 */
 	public Function setParameter(int index, Function var) throws IndexOutOfBoundsException;
 
 	/**
 	 * Generic method to retrieve a parameter in a known position.
-	 * @param index parameter index.
+	 * 
+	 * @param index
+	 *            parameter index.
 	 * @return The requested parameter.
 	 */
 	public Function getParameter(int index) throws IndexOutOfBoundsException;
 
 	/**
 	 * Retrieve the current Math Context used by this function
+	 * 
 	 * @return Calculator mathContext
 	 */
 	public MathContext getMathContext();
@@ -50,6 +58,7 @@ public interface Function {
 
 	/**
 	 * The current simplification status of this function and it's childrens
+	 * 
 	 * @return boolean
 	 */
 	public boolean isSimplified();

src/org/warp/picalculator/math/FunctionDynamic.java

@@ -7,8 +7,6 @@ import java.util.List;
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Utils;
 
-import com.rits.cloning.Cloner;
-
 public abstract class FunctionDynamic implements Function {
 	public FunctionDynamic(MathContext root) {
 		this.root = root;
@@ -37,7 +35,7 @@ public abstract class FunctionDynamic implements Function {
 	}
 
 	public FunctionDynamic setParameters(final List<Function> value) {
-		FunctionDynamic f = this.clone();
+		final FunctionDynamic f = clone();
 		final int vsize = value.size();
 		final Function[] tmp = new Function[vsize];
 		for (int i = 0; i < vsize; i++) {
@@ -48,7 +46,7 @@ public abstract class FunctionDynamic implements Function {
 	}
 
 	public FunctionDynamic setParameters(final Function[] value) {
-		FunctionDynamic f = this.clone();
+		final FunctionDynamic f = clone();
 		f.functions = value;
 		return f;
 	}
@@ -60,13 +58,13 @@ public abstract class FunctionDynamic implements Function {
 
 	@Override
 	public FunctionDynamic setParameter(int index, Function value) {
-		FunctionDynamic f = this.clone();
+		final FunctionDynamic f = clone();
 		f.functions[index] = value;
 		return f;
 	}
 
 	public FunctionDynamic appendParameter(Function value) {
-		FunctionDynamic f = this.clone();
+		final FunctionDynamic f = clone();
 		f.functions = Arrays.copyOf(f.functions, f.functions.length + 1);
 		f.functions[f.functions.length - 1] = value;
 		return f;
@@ -74,6 +72,7 @@ public abstract class FunctionDynamic implements Function {
 
 	/**
 	 * Retrieve the current number of parameters.
+	 * 
 	 * @return The number of parameters.
 	 */
 	public int getParametersLength() {
@@ -81,7 +80,7 @@ public abstract class FunctionDynamic implements Function {
 	}
 
 	public FunctionDynamic setParametersLength(int length) {
-		FunctionDynamic f = this.clone();
+		final FunctionDynamic f = clone();
 		f.functions = Arrays.copyOf(functions, length);
 		return f;
 	}
@@ -97,16 +96,19 @@ public abstract class FunctionDynamic implements Function {
 	}
 
 	/**
-	 * The current simplification status of this function, assuming that its children are already simplified.
+	 * The current simplification status of this function, assuming that its
-	 * @return <strong>true</strong> if this function can be solved, otherwise <strong>false</strong>.
+	 * children are already simplified.
+	 * 
+	 * @return <strong>true</strong> if this function can be solved, otherwise
+	 *         <strong>false</strong>.
 	 */
 	protected abstract boolean isSolvable();
 
 	@Override
 	public final ObjectArrayList<Function> simplify() throws Error {
 		boolean solved = true;
-		Function[] fncs = getParameters();
+		final Function[] fncs = getParameters();
-		for (Function f : fncs) {
+		for (final Function f : fncs) {
 			if (f.isSimplified() == false) {
 				solved = false;
 				break;
@@ -118,12 +120,12 @@ public abstract class FunctionDynamic implements Function {
 			result = new ObjectArrayList<>();
 
 			final ObjectArrayList<ObjectArrayList<Function>> ln = new ObjectArrayList<>();
-			for (int i = 0; i < fncs.length; i++) {
+			for (final Function fnc : fncs) {
-				ObjectArrayList<Function> l = new ObjectArrayList<>();
+				final ObjectArrayList<Function> l = new ObjectArrayList<>();
-				if (fncs[i].isSimplified()) {
+				if (fnc.isSimplified()) {
-					l.add(fncs[i]);
+					l.add(fnc);
 				} else {
-					l.addAll(fncs[i].simplify());
+					l.addAll(fnc.simplify());
 				}
 				ln.add(l);
 			}
@@ -139,9 +141,12 @@ public abstract class FunctionDynamic implements Function {
 	}
 
 	/**
-	 * Solves only this function, assuming that its children are already simplified and it can be solved.
+	 * Solves only this function, assuming that its children are already
+	 * simplified and it can be solved.
+	 * 
 	 * @return The solved function.
-	 * @throws Error Errors during computation, like a/0 or similar.
+	 * @throws Error
+	 *             Errors during computation, like a/0 or similar.
 	 */
 	protected abstract ObjectArrayList<Function> solve() throws Error;
 

src/org/warp/picalculator/math/FunctionOperator.java

@@ -8,24 +8,32 @@ import org.warp.picalculator.Utils;
 public abstract class FunctionOperator implements Function {
 
 	/**
-	 * Create a new instance of FunctionOperator. The Math Context will be the same of <strong>value1</strong>'s.
+	 * Create a new instance of FunctionOperator. The Math Context will be the
-	 * @throws NullPointerException when value1 is null.
+	 * same of <strong>value1</strong>'s.
-	 * @param value1 The parameter of this function.
+	 * 
-	 * @param value2 The parameter of this function.
+	 * @throws NullPointerException
+	 *             when value1 is null.
+	 * @param value1
+	 *            The parameter of this function.
+	 * @param value2
+	 *            The parameter of this function.
 	 */
 	public FunctionOperator(Function value1, Function value2) throws NullPointerException {
-		this.mathContext = value1.getMathContext();
+		mathContext = value1.getMathContext();
 		parameter1 = value1;
 		parameter2 = value2;
 	}
 
 	/**
 	 * Create a new instance of FunctionOperator.
-	 * @param value1 The parameter of this function.
+	 * 
-	 * @param value2 The parameter of this function.
+	 * @param value1
+	 *            The parameter of this function.
+	 * @param value2
+	 *            The parameter of this function.
 	 */
 	public FunctionOperator(MathContext mc, Function value1, Function value2) {
-		this.mathContext = mc;
+		mathContext = mc;
 		parameter1 = value1;
 		parameter2 = value2;
 	}
@@ -53,22 +61,24 @@ public abstract class FunctionOperator implements Function {
 
 	/**
 	 * 
-	 * @param var First parameter.
+	 * @param var
+	 *            First parameter.
 	 * @return A new instance of this function.
 	 */
 	public FunctionOperator setParameter1(Function var) {
-		FunctionOperator s = this.clone();
+		final FunctionOperator s = clone();
 		s.parameter1 = var;
 		return s;
 	}
 
 	/**
 	 * 
-	 * @param var Second parameter.
+	 * @param var
+	 *            Second parameter.
 	 * @return A new instance of this function.
 	 */
 	public FunctionOperator setParameter2(Function var) {
-		FunctionOperator s = this.clone();
+		final FunctionOperator s = clone();
 		s.parameter2 = var;
 		return s;
 	}
@@ -77,9 +87,9 @@ public abstract class FunctionOperator implements Function {
 	public FunctionOperator setParameter(int index, Function var) throws IndexOutOfBoundsException {
 		switch (index) {
 			case 0:
-				return this.setParameter1(var);
+				return setParameter1(var);
 			case 1:
-				return this.setParameter2(var);
+				return setParameter2(var);
 			default:
 				throw new IndexOutOfBoundsException();
 		}
@@ -89,9 +99,9 @@ public abstract class FunctionOperator implements Function {
 	public Function getParameter(int index) throws IndexOutOfBoundsException {
 		switch (index) {
 			case 0:
-				return this.getParameter1();
+				return getParameter1();
 			case 1:
-				return this.getParameter2();
+				return getParameter2();
 			default:
 				throw new IndexOutOfBoundsException();
 		}
@@ -108,8 +118,11 @@ public abstract class FunctionOperator implements Function {
 	}
 
 	/**
-	 * The current simplification status of this function, assuming that its children are already simplified.
+	 * The current simplification status of this function, assuming that its
-	 * @return <strong>true</strong> if this function can be solved, otherwise <strong>false</strong>.
+	 * children are already simplified.
+	 * 
+	 * @return <strong>true</strong> if this function can be solved, otherwise
+	 *         <strong>false</strong>.
 	 */
 	protected abstract boolean isSolvable();
 
@@ -137,7 +150,7 @@ public abstract class FunctionOperator implements Function {
 			final Function[][] results = Utils.joinFunctionsResults(l1, l2);
 
 			for (final Function[] f : results) {
-				result.add(this.setParameter1(f[0]).setParameter2(f[1]));
+				result.add(setParameter1(f[0]).setParameter2(f[1]));
 			}
 		}
 
@@ -145,9 +158,12 @@ public abstract class FunctionOperator implements Function {
 	}
 
 	/**
-	 * Solves only this function, assuming that its children are already simplified and it can be solved.
+	 * Solves only this function, assuming that its children are already
+	 * simplified and it can be solved.
+	 * 
 	 * @return The solved function.
-	 * @throws Error Errors during computation, like a/0 or similar.
+	 * @throws Error
+	 *             Errors during computation, like a/0 or similar.
 	 */
 	protected abstract ObjectArrayList<Function> solve() throws Error;
 

src/org/warp/picalculator/math/FunctionSingle.java

@@ -7,9 +7,13 @@ import org.warp.picalculator.Error;
 public abstract class FunctionSingle implements Function {
 
 	/**
-	 * Create a new instance of FunctionSingle. The Math Context will be the same of <strong>value</strong>'s.
+	 * Create a new instance of FunctionSingle. The Math Context will be the
-	 * @throws NullPointerException when value is null.
+	 * same of <strong>value</strong>'s.
-	 * @param value The parameter of this function.
+	 * 
+	 * @throws NullPointerException
+	 *             when value is null.
+	 * @param value
+	 *            The parameter of this function.
 	 */
 	public FunctionSingle(Function value) throws NullPointerException {
 		mathContext = value.getMathContext();
@@ -18,8 +22,11 @@ public abstract class FunctionSingle implements Function {
 
 	/**
 	 * Create a new instance of FunctionSingle.
-	 * @param mathContext Math Context
+	 * 
-	 * @param value The parameter of this function.
+	 * @param mathContext
+	 *            Math Context
+	 * @param value
+	 *            The parameter of this function.
 	 */
 	public FunctionSingle(MathContext mathContext, Function value) {
 		this.mathContext = mathContext;
@@ -41,13 +48,15 @@ public abstract class FunctionSingle implements Function {
 	public Function getParameter() {
 		return parameter;
 	}
+
 	/**
 	 * 
-	 * @param var Parameter.
+	 * @param var
+	 *            Parameter.
 	 * @return A new instance of this function.
 	 */
 	public FunctionSingle setParameter(Function value) {
-		FunctionSingle s = this.clone();
+		final FunctionSingle s = clone();
 		s.parameter = value;
 		return s;
 	}
@@ -98,11 +107,13 @@ public abstract class FunctionSingle implements Function {
 		return result;
 	}
 
-	
 	/**
-	 * Solves only this function, assuming that its children are already simplified and it can be solved.
+	 * Solves only this function, assuming that its children are already
+	 * simplified and it can be solved.
+	 * 
 	 * @return The solved function.
-	 * @throws Error Errors during computation, like a/0 or similar.
+	 * @throws Error
+	 *             Errors during computation, like a/0 or similar.
 	 */
 	protected abstract ObjectArrayList<Function> solve() throws Error;
 
@@ -112,8 +123,11 @@ public abstract class FunctionSingle implements Function {
 	}
 
 	/**
-	 * The current simplification status of this function, assuming that its children are already simplified.
+	 * The current simplification status of this function, assuming that its
-	 * @return <strong>true</strong> if this function can be solved, otherwise <strong>false</strong>.
+	 * children are already simplified.
+	 * 
+	 * @return <strong>true</strong> if this function can be solved, otherwise
+	 *         <strong>false</strong>.
 	 */
 	protected abstract boolean isSolvable();
 

src/org/warp/picalculator/math/MathContext.java

@@ -12,7 +12,7 @@ import org.warp.picalculator.math.functions.equations.Equation;
 import org.warp.picalculator.math.functions.equations.EquationsSystem;
 
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
-
+import sun.reflect.generics.reflectiveObjects.NotImplementedException;
 
 public class MathContext {
 
@@ -122,4 +122,17 @@ public class MathContext {
 		}
 	}*/
 
+	@Override
+	@Deprecated
+	public MathContext clone() {
+//		MathContext mc = new MathContext();
+//		mc.angleMode = this.angleMode;
+//		mc.exactMode = this.exactMode;
+//		mc.f = this.f;
+//		mc.f2 = this.f2;
+//		mc.variablesValues = this.variablesValues;
+//		mc.resultsCount = this.resultsCount;
+//		return mc;
+		throw new NotImplementedException();
+	}
 }

src/org/warp/picalculator/math/MathematicalSymbols.java

@@ -27,7 +27,6 @@ public class MathematicalSymbols {
 	public static final char ARC_TANGENT = 'Ⓗ';
 	public static final char PI = 'π';
 
-
 	public static final char[] functionsNSN = new char[] { NTH_ROOT, POWER };
 
 	public static final char[] functionsSN = new char[] { SQUARE_ROOT, POWER_OF_TWO, MINUS, SINE, COSINE, TANGENT, ARC_SINE, ARC_COSINE, ARC_TANGENT };

src/org/warp/picalculator/math/functions/Division.java

@@ -3,14 +3,9 @@ package org.warp.picalculator.math.functions;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 import org.warp.picalculator.Error;
-import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.DisplayManager;
-import org.warp.picalculator.gui.GraphicalElement;
-import org.warp.picalculator.gui.graphicengine.cpu.CPUEngine;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionOperator;
-import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.rules.FractionsRule1;
 import org.warp.picalculator.math.rules.FractionsRule11;
 import org.warp.picalculator.math.rules.FractionsRule12;
@@ -26,8 +21,8 @@ public class Division extends FunctionOperator {
 
 	@Override
 	protected boolean isSolvable() {
-		Function variable1 = getParameter1();
+		final Function variable1 = getParameter1();
-		Function variable2 = getParameter2();
+		final Function variable2 = getParameter2();
 		if (FractionsRule1.compare(this)) {
 			return true;
 		}
@@ -50,7 +45,7 @@ public class Division extends FunctionOperator {
 			if (getMathContext().exactMode) {
 				try {
 					return ((Number) variable1).divide((Number) variable2).isInteger();
-				} catch (Error e) {
+				} catch (final Error e) {
 					return false;
 				}
 			} else {
@@ -62,8 +57,8 @@ public class Division extends FunctionOperator {
 
 	@Override
 	public ObjectArrayList<Function> solve() throws Error {
-		Function variable1 = getParameter1();
+		final Function variable1 = getParameter1();
-		Function variable2 = getParameter2();
+		final Function variable2 = getParameter2();
 		ObjectArrayList<Function> result = new ObjectArrayList<>();
 		if (FractionsRule1.compare(this)) {
 			result = FractionsRule1.execute(this);
@@ -94,11 +89,11 @@ public class Division extends FunctionOperator {
 
 	@Override
 	public FunctionOperator clone() {
-		return new Division(this.getMathContext(), this.getParameter1(), this.getParameter2());
+		return new Division(getMathContext(), getParameter1(), getParameter2());
 	}
 
 	@Override
 	public String toString() {
-		return "("+this.getParameter1()+")/("+this.getParameter2()+")";
+		return "(" + getParameter1() + ")/(" + getParameter2() + ")";
 	}
 }

src/org/warp/picalculator/math/functions/EmptyNumber.java

@@ -1,12 +1,7 @@
 package org.warp.picalculator.math.functions;
 
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
-import java.util.List;
-
 import org.warp.picalculator.Error;
-import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.DisplayManager;
-import org.warp.picalculator.gui.graphicengine.cpu.CPUEngine;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 
@@ -18,7 +13,6 @@ public class EmptyNumber implements Function {
 
 	private final MathContext root;
 
-
 	@Override
 	public ObjectArrayList<Function> simplify() throws Error {
 		// TODO Auto-generated method stub

src/org/warp/picalculator/math/functions/Expression.java

@@ -12,7 +12,6 @@ import java.util.regex.Pattern;
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Errors;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionDynamic;
@@ -628,7 +627,7 @@ public class Expression extends FunctionDynamic {
 	public String toString() {
 		String s = "(";
 		if (functions.length > 0) {
-			for (Function f : functions) {
+			for (final Function f : functions) {
 				if (f == null) {
 					s += "[null],";
 				} else {

src/org/warp/picalculator/math/functions/Joke.java

@@ -1,13 +1,7 @@
 package org.warp.picalculator.math.functions;
 
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
-import java.util.List;
-
 import org.warp.picalculator.Error;
-import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.DisplayManager;
-import org.warp.picalculator.gui.graphicengine.BinaryFont;
-import org.warp.picalculator.gui.graphicengine.cpu.CPUEngine;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 

src/org/warp/picalculator/math/functions/Multiplication.java

@@ -5,9 +5,7 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 import org.warp.picalculator.Error;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
-import org.warp.picalculator.math.FunctionSingle;
 import org.warp.picalculator.math.FunctionOperator;
-import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.rules.ExponentRule15;
 import org.warp.picalculator.math.rules.ExponentRule16;
 import org.warp.picalculator.math.rules.FractionsRule14;
@@ -29,8 +27,8 @@ public class Multiplication extends FunctionOperator {
 
 	@Override
 	protected boolean isSolvable() {
-		Function variable1 = getParameter1();
+		final Function variable1 = getParameter1();
-		Function variable2 = getParameter2();
+		final Function variable2 = getParameter2();
 		if (variable1 instanceof Number & variable2 instanceof Number) {
 			return true;
 		}

src/org/warp/picalculator/math/functions/Negative.java

@@ -4,13 +4,9 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Errors;
-import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.DisplayManager;
-import org.warp.picalculator.gui.graphicengine.cpu.CPUEngine;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionSingle;
-import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.rules.ExpandRule1;
 import org.warp.picalculator.math.rules.ExpandRule5;
 

src/org/warp/picalculator/math/functions/Number.java

@@ -7,16 +7,11 @@ import java.util.LinkedList;
 import java.util.List;
 
 import org.nevec.rjm.BigDecimalMath;
-import org.nevec.rjm.BigIntegerMath;
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.DisplayManager;
-import org.warp.picalculator.gui.graphicengine.BinaryFont;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 
-import com.rits.cloning.Cloner;
-
 public class Number implements Function {
 
 	private final MathContext root;
@@ -123,9 +118,9 @@ public class Number implements Function {
 	public List<Function> simplify() throws Error {
 		final List<Function> result = new ObjectArrayList<>();
 		if (root.exactMode) {
-			Number divisor = new Number(root, BigInteger.TEN.pow(getNumberOfDecimalPlaces()));
+			final Number divisor = new Number(root, BigInteger.TEN.pow(getNumberOfDecimalPlaces()));
-			Number numb = new Number(root, term.multiply(divisor.term));
+			final Number numb = new Number(root, term.multiply(divisor.term));
-			Division div = new Division(root, numb, divisor);
+			final Division div = new Division(root, numb, divisor);
 			result.add(div);
 		} else {
 			result.add(this);

src/org/warp/picalculator/math/functions/Power.java

@@ -6,7 +6,6 @@ import org.warp.picalculator.Error;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionOperator;
-import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.rules.ExponentRule1;
 import org.warp.picalculator.math.rules.ExponentRule2;
 import org.warp.picalculator.math.rules.ExponentRule3;

src/org/warp/picalculator/math/functions/Root.java

@@ -5,11 +5,9 @@ import java.math.BigInteger;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 import org.warp.picalculator.Error;
-import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionOperator;
-import org.warp.picalculator.math.MathematicalSymbols;
 
 public class Root extends FunctionOperator {
 

src/org/warp/picalculator/math/functions/RootSquare.java

@@ -4,11 +4,9 @@ import java.math.BigInteger;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 import org.warp.picalculator.Error;
-import org.warp.picalculator.Utils;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionSingle;
-import org.warp.picalculator.math.MathematicalSymbols;
 
 public class RootSquare extends FunctionSingle {
 

src/org/warp/picalculator/math/functions/Subtraction.java

@@ -6,7 +6,6 @@ import org.warp.picalculator.Error;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionOperator;
-import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.rules.ExpandRule1;
 import org.warp.picalculator.math.rules.ExpandRule5;
 import org.warp.picalculator.math.rules.NumberRule3;

src/org/warp/picalculator/math/functions/Sum.java

@@ -5,12 +5,9 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Errors;
-import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionOperator;
-import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.rules.NumberRule3;
 import org.warp.picalculator.math.rules.NumberRule5;
 import org.warp.picalculator.math.rules.NumberRule7;

src/org/warp/picalculator/math/functions/SumSubtraction.java

@@ -4,13 +4,9 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Errors;
-import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.DisplayManager;
-import org.warp.picalculator.gui.graphicengine.cpu.CPUEngine;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionOperator;
-import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.rules.ExpandRule1;
 import org.warp.picalculator.math.rules.NumberRule3;
 import org.warp.picalculator.math.rules.NumberRule4;

src/org/warp/picalculator/math/functions/Undefined.java

@@ -3,9 +3,6 @@ package org.warp.picalculator.math.functions;
 import java.util.List;
 
 import org.warp.picalculator.Error;
-import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.DisplayManager;
-import org.warp.picalculator.gui.graphicengine.cpu.CPUEngine;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 

src/org/warp/picalculator/math/functions/Variable.java

@@ -4,13 +4,9 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 import java.util.List;
 
 import org.warp.picalculator.Error;
-import org.warp.picalculator.Utils;
-import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 
-import com.rits.cloning.Cloner;
-
 public class Variable implements Function {
 
 	protected char var;
@@ -94,9 +90,7 @@ public class Variable implements Function {
 	}
 
 	public static enum V_TYPE {
-		KNOWN,
+		KNOWN, UNKNOWN, SOLUTION
-		UNKNOWN,
-		SOLUTION
 	}
 
 	@Override

src/org/warp/picalculator/math/functions/equations/Equation.java

@@ -11,13 +11,10 @@ import org.warp.picalculator.Errors;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionOperator;
-import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.SolveMethod;
 import org.warp.picalculator.math.functions.Number;
 import org.warp.picalculator.math.functions.Subtraction;
 
-import com.rits.cloning.Cloner;
-
 public class Equation extends FunctionOperator {
 
 	public Equation(MathContext root, Function value1, Function value2) {
@@ -81,8 +78,7 @@ public class Equation extends FunctionOperator {
 
 	@Override
 	public Equation clone() {
-		final Cloner cloner = new Cloner();
+		return new Equation(mathContext, parameter1, parameter2);
-		return cloner.deepClone(this);
 	}
 
 	@Override

src/org/warp/picalculator/math/functions/equations/EquationsSystem.java

@@ -4,7 +4,6 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 import java.util.List;
 
 import org.warp.picalculator.Error;
-import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionDynamic;

src/org/warp/picalculator/math/functions/equations/EquationsSystemPart.java

@@ -1,14 +1,10 @@
 package org.warp.picalculator.math.functions.equations;
 
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
-import java.util.List;
-
 import org.warp.picalculator.Error;
-import org.warp.picalculator.gui.DisplayManager;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionSingle;
-import org.warp.picalculator.math.MathematicalSymbols;
 
 public class EquationsSystemPart extends FunctionSingle {
 

src/org/warp/picalculator/math/functions/trigonometry/ArcCosine.java

@@ -6,7 +6,6 @@ import org.warp.picalculator.Error;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionSingle;
-import org.warp.picalculator.math.MathematicalSymbols;
 
 public class ArcCosine extends FunctionSingle {
 

src/org/warp/picalculator/math/functions/trigonometry/ArcSine.java

@@ -6,7 +6,6 @@ import org.warp.picalculator.Error;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionSingle;
-import org.warp.picalculator.math.MathematicalSymbols;
 
 public class ArcSine extends FunctionSingle {
 

src/org/warp/picalculator/math/functions/trigonometry/ArcTangent.java

@@ -6,7 +6,6 @@ import org.warp.picalculator.Error;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionSingle;
-import org.warp.picalculator.math.MathematicalSymbols;
 
 public class ArcTangent extends FunctionSingle {
 

src/org/warp/picalculator/math/functions/trigonometry/Cosine.java

@@ -6,7 +6,6 @@ import org.warp.picalculator.Error;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionSingle;
-import org.warp.picalculator.math.MathematicalSymbols;
 
 public class Cosine extends FunctionSingle {
 

src/org/warp/picalculator/math/functions/trigonometry/Sine.java

@@ -8,7 +8,6 @@ import org.warp.picalculator.math.AngleMode;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionSingle;
-import org.warp.picalculator.math.MathematicalSymbols;
 import org.warp.picalculator.math.functions.Number;
 
 public class Sine extends FunctionSingle {

src/org/warp/picalculator/math/functions/trigonometry/Tangent.java

@@ -6,7 +6,6 @@ import org.warp.picalculator.Error;
 import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionSingle;
-import org.warp.picalculator.math.MathematicalSymbols;
 
 public class Tangent extends FunctionSingle {
 

src/org/warp/picalculator/math/parser/MathParser.java

@@ -1,11 +1,16 @@
 package org.warp.picalculator.math.parser;
 
+import java.math.BigDecimal;
+import java.math.BigInteger;
+import java.util.Arrays;
+
 import org.warp.picalculator.Error;
 import org.warp.picalculator.Errors;
 import org.warp.picalculator.gui.expression.Block;
 import org.warp.picalculator.gui.expression.BlockChar;
 import org.warp.picalculator.gui.expression.BlockContainer;
 import org.warp.picalculator.gui.expression.BlockDivision;
+import org.warp.picalculator.gui.expression.containers.InputContainer;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.FunctionOperator;
 import org.warp.picalculator.math.FunctionSingle;
@@ -15,6 +20,8 @@ import org.warp.picalculator.math.functions.Number;
 import org.warp.picalculator.math.functions.Subtraction;
 import org.warp.picalculator.math.functions.Sum;
 import org.warp.picalculator.math.functions.SumSubtraction;
+import org.warp.picalculator.math.functions.Variable;
+import org.warp.picalculator.math.functions.Variable.V_TYPE;
 import org.warp.picalculator.math.functions.Division;
 import org.warp.picalculator.math.functions.Expression;
 import org.warp.picalculator.math.functions.Multiplication;
@@ -23,6 +30,7 @@ import org.warp.picalculator.math.parser.features.FeatureDivision;
 import org.warp.picalculator.math.parser.features.FeatureMultiplication;
 import org.warp.picalculator.math.parser.features.FeatureNumber;
 import org.warp.picalculator.math.parser.features.FeatureSum;
+import org.warp.picalculator.math.parser.features.FeatureVariable;
 import org.warp.picalculator.math.parser.features.interfaces.Feature;
 import org.warp.picalculator.math.parser.features.interfaces.FeatureDouble;
 
@@ -30,27 +38,67 @@ import com.sun.org.apache.xpath.internal.functions.Function2Args;
 
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 import it.unimi.dsi.fastutil.objects.ObjectListIterator;
+import sun.reflect.generics.reflectiveObjects.NotImplementedException;
 
 public class MathParser {
-	public static Expression parseInput(MathContext context, BlockContainer root) throws Error {
+	public static Expression parseInput(MathContext context, InputContainer c) throws Error {
 		Expression result;
 
-		Function resultFunction = parseContainer(context, root);
+		final Function resultFunction = parseContainer(context, c.getContent());
 
 		result = new Expression(context, resultFunction);
 		return result;
 	}
 
-	private static Function parseContainer(final MathContext context, final BlockContainer container) throws Error {
+	public static ObjectArrayList<Block> parseOutput(MathContext context, ObjectArrayList<Function> expr) {
-		final ObjectArrayList<Block> blocks = container.getContent();
+		final ObjectArrayList<Block> resultBlocks = new ObjectArrayList<>();
+		
+		for (Function f : expr) {
+			resultBlocks.addAll(parseFunction(context, f));
+		}
+		
+		return resultBlocks;
+	}
+	
+	private static ObjectArrayList<Block> parseFunction(MathContext context, Function func) {
+		ObjectArrayList<Block> result = new ObjectArrayList<>();
+		if (func instanceof FunctionOperator) {
+			ObjectArrayList<Block> sub1 = parseFunction(context, func.getParameter(0));
+			ObjectArrayList<Block> sub2 = parseFunction(context, func.getParameter(1));
+			if (func instanceof Sum) {
+				result.addAll(sub1);
+				result.add(new BlockChar(MathematicalSymbols.SUM));
+				result.addAll(sub2);
+				return result;
+			}
+		}
+		if (func instanceof Number) {
+			Number numb = (Number) func;
+			BigDecimal decimal = numb.getTerm();
+			String numberString;
+			if (numb.isInteger()) {
+				BigInteger integ = decimal.toBigInteger();
+				numberString = integ.toString();
+			} else {
+				numberString = decimal.toPlainString();
+			}
+			for (char c : numberString.toCharArray()) {
+				result.add(new BlockChar(c));
+			}
+			return result;
+		}
+		throw new UnsupportedOperationException("Unknown function " + func.getClass().getSimpleName());
+	}
+
+	private static Function parseContainer(final MathContext context, final Iterable<Block> blocks) throws Error {
 		final ObjectArrayList<Feature> blockFeatures = new ObjectArrayList<>();
 
 		for (final Block block : blocks) {
-			Feature blockFeature = parseBlock(context, block);
+			final Feature blockFeature = parseBlock(context, block);
 			blockFeatures.add(blockFeature);
 		}
 
-		Function result = joinFeatures(context, blockFeatures);
+		final Function result = joinFeatures(context, blockFeatures);
 		return result;
 	}
 
@@ -58,15 +106,15 @@ public class MathParser {
 
 		Feature result;
 
-		int blockType = block.getClassID();
+		final int blockType = block.getClassID();
 		switch (blockType) {
 			case BlockChar.CLASS_ID:
 				result = new FeatureChar(((BlockChar) block).getChar());
 				break;
 			case BlockDivision.CLASS_ID:
-				BlockDivision bd = (BlockDivision) block;
+				final BlockDivision bd = (BlockDivision) block;
-				Function upper = parseContainer(context, bd.getUpperContainer());
+				final Function upper = parseContainer(context, bd.getUpperContainer().getContent());
-				Function lower = parseContainer(context, bd.getLowerContainer());
+				final Function lower = parseContainer(context, bd.getLowerContainer().getContent());
 				result = new FeatureDivision(upper, lower);
 				break;
 			default:
@@ -80,7 +128,7 @@ public class MathParser {
 
 		features = fixFeatures(context, features);
 
-		ObjectArrayList<Function> process = makeFunctions(context, features);
+		final ObjectArrayList<Function> process = makeFunctions(context, features);
 
 		fixStack(context, process);
 
@@ -97,7 +145,7 @@ public class MathParser {
 		ObjectListIterator<Function> stackIterator = process.listIterator(process.size());
 		Function lastElement = null;
 		while (stackIterator.hasPrevious()) {
-			Function f = stackIterator.previous();
+			final Function f = stackIterator.previous();
 
 			if (f instanceof FunctionSingle) {
 				if (((FunctionSingle) f).getParameter() == null) {
@@ -115,17 +163,14 @@ public class MathParser {
 		//Phase 2
 		stackIterator = process.listIterator();
 		while (stackIterator.hasNext()) {
-			Function f = stackIterator.next();
+			final Function f = stackIterator.next();
 			final int curIndex = stackIterator.previousIndex();
 
 			if (f instanceof Multiplication || f instanceof Division) {
 				if (curIndex - 1 >= 0 && stackIterator.hasNext()) {
-					Function next = process.get(curIndex+1);
+					final Function next = process.get(curIndex + 1);
-					Function prev = process.get(curIndex-1);
+					final Function prev = process.get(curIndex - 1);
-					stackIterator.set(
+					stackIterator.set(f.setParameter(0, prev).setParameter(1, next));
-					f.setParameter(0, prev)
-					.setParameter(1, next)
-					);
 					process.remove(curIndex + 1);
 					process.remove(curIndex - 1);
 				} else {
@@ -139,17 +184,28 @@ public class MathParser {
 		//Phase 3
 		stackIterator = process.listIterator();
 		while (stackIterator.hasNext()) {
-			Function f = stackIterator.next();
+			final Function f = stackIterator.next();
+			final int curIndex = stackIterator.previousIndex();
 
 			if (f instanceof Sum || f instanceof Subtraction || f instanceof SumSubtraction) {
-				
+				if (curIndex - 1 >= 0 && stackIterator.hasNext()) {
+					final Function next = process.get(curIndex + 1);
+					final Function prev = process.get(curIndex - 1);
+					stackIterator.set(f.setParameter(0, prev).setParameter(1, next));
+					process.remove(curIndex + 1);
+					process.remove(curIndex - 1);
+				} else {
+					if (f.getParameter(0) == null || f.getParameter(1) == null) {
+						throw new Error(Errors.MISSING_ARGUMENTS, "There is a function at the end without any argument specified.");
+					}
+				}
 			}
 		}
 
 		//Phase 4
 		stackIterator = process.iterator();
 		while (stackIterator.hasNext()) {
-			Function f = stackIterator.next();
+			final Function f = stackIterator.next();
 
 			if (f instanceof Function2Args) {
 
@@ -157,27 +213,37 @@ public class MathParser {
 		}
 	}
 
-	private static ObjectArrayList<Function> makeFunctions(MathContext context, ObjectArrayList<Feature> features) throws Error {
+	private static ObjectArrayList<Function> makeFunctions(MathContext context, ObjectArrayList<Feature> features)
-		ObjectArrayList<Function> process = new ObjectArrayList<>();
+			throws Error {
+		final ObjectArrayList<Function> process = new ObjectArrayList<>();
 
-		for (Feature f : features) {
+		for (final Feature f : features) {
 			if (f instanceof FeatureDivision) {
 				process.add(new Division(context, (Function) ((FeatureDouble) f).getChild1(), (Function) ((FeatureDouble) f).getChild2()));
 			} else if (f instanceof FeatureMultiplication) {
 				process.add(new Multiplication(context, (Function) ((FeatureDouble) f).getChild1(), (Function) ((FeatureDouble) f).getChild2()));
+			} else if (f instanceof FeatureVariable) {
+				process.add(new Variable(context, ((FeatureVariable) f).ch, ((FeatureVariable) f).varType));
+			} else if (f instanceof FeatureSum) {
+				process.add(new Sum(context, (Function) ((FeatureDouble) f).getChild1(), (Function) ((FeatureDouble) f).getChild2()));
+//			}  else if (f instanceof FeatureSubtraction) {
+//				process.add(new Subtraction(context, (Function) ((FeatureDouble) f).getChild1(), (Function) ((FeatureDouble) f).getChild2()));
+//			}  else if (f instanceof FeatureSumSubtraction) {
+//				process.add(new SumSubtraction(context, (Function) ((FeatureDouble) f).getChild1(), (Function) ((FeatureDouble) f).getChild2()));
 			} else if (f instanceof FeatureNumber) {
 				process.add(new Number(context, ((FeatureNumber) f).getNumberString()));
 			} else if (f instanceof FeatureChar) {
 				//All the char features must have been changed already before
-				throw new Error(Errors.SYNTAX_ERROR, "\"" + f.getClass().getSimpleName().toString() + "\" can't be converted into a Function!");
+				throw new Error(Errors.SYNTAX_ERROR, "\"" + f.getClass().getSimpleName() + "\" can't be converted into a Function!");
 			} else {
-				throw new Error(Errors.SYNTAX_ERROR, "\"" + f.getClass().getSimpleName().toString() + "\" can't be converted into a Function!");
+				throw new Error(Errors.SYNTAX_ERROR, "\"" + f.getClass().getSimpleName() + "\" can't be converted into a Function!");
 			}
 		}
 		return process;
 	}
 
-	private static ObjectArrayList<Feature> fixFeatures(final MathContext context, ObjectArrayList<Feature> features) throws Error {
+	private static ObjectArrayList<Feature> fixFeatures(final MathContext context, ObjectArrayList<Feature> features)
+			throws Error {
 
 		features = fixMinuses(context, features);
 
@@ -190,14 +256,16 @@ public class MathParser {
 
 	/**
 	 * Create function features from char features
+	 * 
 	 * @param context
 	 * @param features
 	 * @return
 	 */
-	private static ObjectArrayList<Feature> convertFunctionChars(MathContext context, ObjectArrayList<Feature> features) throws Error {
+	private static ObjectArrayList<Feature> convertFunctionChars(MathContext context, ObjectArrayList<Feature> features)
-		ObjectArrayList<Feature> process = new ObjectArrayList<>();
+			throws Error {
+		final ObjectArrayList<Feature> process = new ObjectArrayList<>();
 
-		for (Feature f : features) {
+		for (final Feature f : features) {
 			if (f instanceof FeatureChar) {
 				final char featureChar = ((FeatureChar) f).ch;
 				Feature result = null;
@@ -210,6 +278,14 @@ public class MathParser {
 						break;
 				}
 				
+				//TODO: Temporary solution. In near future Variables will be distint objects and they will have a color. So they will be no longer a BlockChar/FeatureChar
+				for (char var : MathematicalSymbols.variables) {
+					if ( featureChar == var) {
+						result = new FeatureVariable(featureChar, V_TYPE.UNKNOWN);
+						break;
+					}
+				}
+
 				if (result == null) {
 					throw new Error(Errors.SYNTAX_ERROR, "Char " + featureChar + " isn't a known feature");
 				}
@@ -225,20 +301,21 @@ public class MathParser {
 
 	/**
 	 * Make numbers [-][1][2][+][-][3] => [-12]
+	 * 
 	 * @param context
 	 * @param features
 	 * @return
 	 */
 	private static ObjectArrayList<Feature> makeNumbers(MathContext context, ObjectArrayList<Feature> features) {
-		ObjectArrayList<Feature> process = new ObjectArrayList<>();
+		final ObjectArrayList<Feature> process = new ObjectArrayList<>();
 
 		FeatureNumber numberBuffer = null;
-		for (Feature f : features) {
+		for (final Feature f : features) {
 			if (f instanceof FeatureChar) {
 				final FeatureChar bcf = (FeatureChar) f;
 				final char[] numbers = MathematicalSymbols.numbers;
 				boolean isNumber = false;
-				for (char n : numbers) {
+				for (final char n : numbers) {
 					if (bcf.ch == n) {
 						isNumber = true;
 						break;
@@ -270,23 +347,25 @@ public class MathParser {
 
 	/**
 	 * Fix minuses [-][1][2][+][-][3][-][2] => [-][12][+][-][3][—][2]
+	 * 
 	 * @param context
 	 * @param features
 	 * @return
 	 * @throws Error
 	 */
-	private static ObjectArrayList<Feature> fixMinuses(final MathContext context, ObjectArrayList<Feature> features) throws Error {
+	private static ObjectArrayList<Feature> fixMinuses(final MathContext context, ObjectArrayList<Feature> features)
-		ObjectArrayList<Feature> process = new ObjectArrayList<>();
+			throws Error {
+		final ObjectArrayList<Feature> process = new ObjectArrayList<>();
 		Feature lastFeature = null;
-		for (Feature f : features) {
+		for (final Feature f : features) {
 			if (f instanceof FeatureChar && ((FeatureChar) f).ch == MathematicalSymbols.SUBTRACTION) {
 				boolean isNegativeOfNumber = false;
 				if (lastFeature == null) {
 					isNegativeOfNumber = true;
 				} else if (lastFeature instanceof FeatureChar) {
-					FeatureChar lcf = (FeatureChar) lastFeature;
+					final FeatureChar lcf = (FeatureChar) lastFeature;
 					final char[] operators = MathematicalSymbols.functionsNSN;
-					for (char operator : operators) {
+					for (final char operator : operators) {
 						if (lcf.ch == operator) {
 							isNegativeOfNumber = true;
 							break;

src/org/warp/picalculator/math/parser/features/FeatureVariable.java

@@ -0,0 +1,15 @@
+package org.warp.picalculator.math.parser.features;
+
+import org.warp.picalculator.math.functions.Variable.V_TYPE;
+import org.warp.picalculator.math.parser.features.interfaces.Feature;
+
+public class FeatureVariable extends FeatureChar {
+
+	public V_TYPE varType;
+
+	public FeatureVariable(char ch, V_TYPE varType) {
+		super(ch);
+		this.varType = varType;
+	}
+
+}

src/org/warp/picalculator/math/parser/features/interfaces/FeatureBasic.java

@@ -1,4 +1,3 @@
 package org.warp.picalculator.math.parser.features.interfaces;
 
-public interface FeatureBasic extends Feature {
+public interface FeatureBasic extends Feature {}
-}

src/org/warp/picalculator/math/parser/features/interfaces/FeatureDouble.java

@@ -2,7 +2,10 @@ package org.warp.picalculator.math.parser.features.interfaces;
 
 public interface FeatureDouble extends Feature {
 	public Object getChild1();
+
 	public void setChild1(Object obj);
+
 	public Object getChild2();
+
 	public void setChild2(Object obj);
 }

src/org/warp/picalculator/math/parser/features/interfaces/FeatureMultiple.java

@@ -2,9 +2,14 @@ package org.warp.picalculator.math.parser.features.interfaces;
 
 public interface FeatureMultiple extends Feature {
 	public Object[] getChildren();
+
 	public Object getChild(int index);
+
 	public int getChildCount();
+
 	public void setChild(int index, Object obj);
+
 	public void setChildren(Object[] objs);
+
 	public void addChild(Object obj);
 }

src/org/warp/picalculator/math/parser/features/interfaces/FeatureSingle.java

@@ -2,5 +2,6 @@ package org.warp.picalculator.math.parser.features.interfaces;
 
 public interface FeatureSingle extends Feature {
 	public Object getChild();
+
 	public void setChild(Object obj);
 }

src/org/warp/picalculator/math/rules/ExponentRule9.java

@@ -7,7 +7,6 @@ import org.warp.picalculator.math.MathContext;
 import org.warp.picalculator.math.Function;
 import org.warp.picalculator.math.functions.Expression;
 import org.warp.picalculator.math.functions.Multiplication;
-import org.warp.picalculator.math.functions.Number;
 import org.warp.picalculator.math.functions.Power;
 
 /**

src/org/warp/picalculator/math/rules/FractionsRule11.java

@@ -39,7 +39,7 @@ public class FractionsRule11 {
 		Function b;
 		Function c;
 
-		Division div2 = (Division) fnc.getParameter2();
+		final Division div2 = (Division) fnc.getParameter2();
 
 		a = fnc.getParameter1();
 		b = div2.getParameter1();

src/org/warp/picalculator/math/rules/VariableRule2.java

@@ -38,7 +38,6 @@ public class VariableRule2 {
 		final Function a = m1.getParameter1();
 		final Function x = fnc.getParameter2();
 
-
 		FunctionOperator rets;
 		if (fnc instanceof Sum) {
 			rets = new Sum(root, a, new Number(root, 1));