Add comments to incorrect rules and partially fix ExpandRule1

This commit is contained in:
Riccardo Azzolini 2019-02-09 18:37:58 +01:00
parent df5de92931
commit 6b814b84b6
2 changed files with 27 additions and 21 deletions

View File

@ -50,33 +50,33 @@ public class ExpandRule1 implements Rule {
if (fnc.getParameter1().equals(new Number(fnc.getMathContext(), -1))) {
final Function expr = fnc.getParameter2();
if (expr instanceof Sum)
isExecutable = true;
isExecutable = true; // -1 * (a + b)
else if (expr instanceof Subtraction)
isExecutable = true;
isExecutable = true; // -1 * (a - b)
else if (expr instanceof SumSubtraction)
isExecutable = true;
isExecutable = true; // -1 * (a +- b)
}
} else if (f instanceof Subtraction || f instanceof SumSubtraction) {
final FunctionOperator fnc = (FunctionOperator) f;
final Function expr = fnc.getParameter2();
if (expr instanceof Sum)
isExecutable = true;
isExecutable = true; // x [- +-] (a + b)
else if (expr instanceof Subtraction)
isExecutable = true;
isExecutable = true; // x [- +-] (a - b)
else if (expr instanceof SumSubtraction)
isExecutable = true;
isExecutable = true; // x [- +-] (a +- b)
}
if (isExecutable) {
final ObjectArrayList<Function> result = new ObjectArrayList<>();
final MathContext root = f.getMathContext();
Function expr = null;
int fromSubtraction = 0;
Function expr = null; // f.getParameter1() [* - +-] expr
int fromSubtraction = 0; // 0: (*), 1: (-), 2: (+-)
FunctionOperator subtraction = null;
if (f instanceof Multiplication)
expr = ((Multiplication) f).getParameter2();
else if (f instanceof Subtraction || f instanceof SumSubtraction) {
expr = ((Multiplication) f).getParameter2();
expr = ((FunctionOperator) f).getParameter2();
if (f instanceof Subtraction)
fromSubtraction = 1;
else
@ -93,31 +93,37 @@ public class ExpandRule1 implements Rule {
final Function b = ((Sum) fnc).getParameter2();
final Function fnc2 = new Subtraction(root, new Multiplication(root, new Number(root, -1), a), b);
if (fromSubtraction > 0) {
subtraction = new Subtraction(root, ((FunctionOperator) f).getParameter1(), fnc2);
result.add(subtraction);
// FIXME SumSubtraction treated as just Subtraction
subtraction = new Sum(root, ((FunctionOperator) f).getParameter1(), fnc2);
result.add(subtraction); // x [- +-] (a + b) -> x + (-1*a - b)
} else
result.add(fnc2);
result.add(fnc2); // -1 * (a + b) -> -1*a - b
} else if (fnc instanceof Subtraction) {
final Function a = ((Subtraction) fnc).getParameter1();
final Function b = ((Subtraction) fnc).getParameter2();
final Function fnc2 = new Sum(root, new Multiplication(root, new Number(root, -1), a), b);
if (fromSubtraction > 0) {
subtraction = new Subtraction(root, ((FunctionOperator) f).getParameter1(), fnc2);
result.add(subtraction);
// FIXME SumSubtraction treated as just Subtraction
subtraction = new Sum(root, ((FunctionOperator) f).getParameter1(), fnc2);
result.add(subtraction); // x [- +-] (a - b) -> x + (-1*a + b)
} else
result.add(fnc2);
} else if (fnc instanceof SumSubtraction) {
result.add(fnc2); // -1 * (a - b) -> -1*a + b
} else if (fnc instanceof SumSubtraction) { // FIXME Subtraction and SumSubtraction confusion
final Function a = ((SumSubtraction) fnc).getParameter1();
final Function b = ((SumSubtraction) fnc).getParameter2();
final Function fnc2 = new Sum(root, new Multiplication(root, new Number(root, -1), a), b);
final Function fnc3 = new Subtraction(root, new Multiplication(root, new Number(root, -1), a), b);
final Function fnc2 = new Sum(root, new Multiplication(root, new Number(root, -1), a), b); // -1*a + b
final Function fnc3 = new Subtraction(root, new Multiplication(root, new Number(root, -1), a), b); // -1*a - b
if (fromSubtraction > 0) {
// x [- +-] (a +- b) -> [x +- (-1*a + b), x +- (-1*a - b), x +- (-1*a - b)]
subtraction = new SumSubtraction(root, ((FunctionOperator) f).getParameter1(), fnc2);
result.add(subtraction);
subtraction = new SumSubtraction(root, ((FunctionOperator) f).getParameter1(), fnc3);
// FIXME same result twice
result.add(subtraction);
result.add(subtraction);
} else {
// -1 * (a +- b) -> [-1*a + b, -1*a + b]
// FIXME same result twice
result.add(fnc2);
result.add(fnc2);
}

View File

@ -41,12 +41,12 @@ public class ExponentRule17 implements Rule {
*/
@Override
public ObjectArrayList<Function> execute(final Function f) {
public ObjectArrayList<Function> execute(final Function f) { // FIXME incorrect rule
boolean isExecutable = false;
if (f instanceof Root) {
final FunctionOperator fnc = (FunctionOperator) f;
if (fnc.getParameter1().equals(fnc.getParameter2()))
isExecutable = true;
isExecutable = true; // root(a, a)
}
if (isExecutable) {
@ -57,7 +57,7 @@ public class ExponentRule17 implements Rule {
final Function two = new Number(root, 2);
final Function p = new Power(root, a, two);
result.add(p);
return result;
return result; // root(a, a) -> a^2
} else
return null;
}