From 665ac263335f9d911113e9472058d505fde605e9 Mon Sep 17 00:00:00 2001
From: Vinzent Steinberg <Vinzent.Steinberg@gmail.com>
Date: Fri, 5 May 2017 13:22:45 +0200
Subject: [PATCH] Add some benchmarks

---
 Cargo.toml |  1 +
 src/lib.rs | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/Cargo.toml b/Cargo.toml
index e562795..e031ab2 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,3 +13,4 @@ conv = "0.3"
 
 [dev-dependencies]
 rand = "0.3"
+streaming-stats = "0.1"
diff --git a/src/lib.rs b/src/lib.rs
index 9314db9..5d00ada 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,8 +1,11 @@
 #![no_std]
+#![feature(test)]
 
 extern crate conv;
 #[cfg(test)] extern crate rand;
 #[cfg(test)] #[macro_use] extern crate std;
+#[cfg(test)] extern crate stats;
+#[cfg(test)] extern crate test;
 
 use conv::ApproxFrom;
 
@@ -90,6 +93,8 @@ impl core::iter::FromIterator<f64> for Average {
 mod tests {
     use super::*;
 
+    use std::vec::Vec;
+
     use ::conv::ConvAsUtil;
 
     #[test]
@@ -123,4 +128,35 @@ mod tests {
         assert_almost_eq!(a.avg(), 2.0, 1e-2);
         assert_almost_eq!(a.var().sqrt(), 3.0, 1e-2);
     }
+
+    fn initialize_vec() -> Vec<f64> {
+        use rand::distributions::{Normal, IndependentSample};
+        use rand::{XorShiftRng, SeedableRng};
+        let normal = Normal::new(2.0, 3.0);
+        let n = 1_000_000;
+        let mut values = Vec::with_capacity(n);
+        let mut rng = XorShiftRng::from_seed([1, 2, 3, 4]);
+        for _ in 0..n {
+            values.push(normal.ind_sample(&mut rng));
+        }
+        values
+    }
+
+    #[bench]
+    fn bench_average(b: &mut test::Bencher) {
+        let values = initialize_vec();
+        b.iter(|| {
+            let a: Average = values.iter().map(|x| *x).collect();
+            a
+        });
+    }
+
+    #[bench]
+    fn bench_stats(b: &mut test::Bencher) {
+        let values = initialize_vec();
+        b.iter(|| {
+            let a: stats::OnlineStats = values.iter().map(|x| *x).collect();
+            a
+        });
+    }
 }