From 28f7497e0a73583fe10a6e9a4d38fa0d4f0bb161 Mon Sep 17 00:00:00 2001
From: Joshua Moerman <lakseru@gmail.com>
Date: Mon, 13 Jan 2014 15:40:38 +0100
Subject: [PATCH] Cleans up a bit, adds options for iterations

---
 wavelet/wavelet_parallel_mockup.cpp | 64 +++++++++++------------------
 1 file changed, 23 insertions(+), 41 deletions(-)

diff --git a/wavelet/wavelet_parallel_mockup.cpp b/wavelet/wavelet_parallel_mockup.cpp
index f8d027e..7134a66 100644
--- a/wavelet/wavelet_parallel_mockup.cpp
+++ b/wavelet/wavelet_parallel_mockup.cpp
@@ -7,7 +7,7 @@
 #include "wavelet_parallel.hpp"
 
 // Number of iterations to improve time measurements
-const unsigned int ITERS = 1;
+static unsigned int ITERS = 1;
 
 // Static :(, will be set in main
 static unsigned int P;
@@ -101,46 +101,20 @@ static void seq_wavelet(){
 	std::copy(v.begin(), v.end(), seq_result.begin());
 }
 
-// Checks whether seq and par agree
-// NOTE: modifies the global par_result
-static void check_equality(double threshold){
-	if(par_result == seq_result){
-		std::cout << colors::green("SUCCES:") << " Results are bitwise equal" << std::endl;
-	} else {
-		for(unsigned int i = 0; i < N; ++i){
-			auto sq = par_result[i] - seq_result[i];
-			par_result[i] = sq*sq;
-		}
-		auto rmse = std::sqrt(std::accumulate(par_result.begin(), par_result.end(), 0.0) / N);
-		if(rmse <= threshold){
-			std::cout << colors::green("SUCCES:") << " Results are almost the same: rmse = " << rmse << std::endl;
-		} else {
-			std::cout << colors::red("FAIL:") << " Results differ: rmse = " << rmse << std::endl;
-		}
-	}
-}
+// square difference, used to calculate root mean squared error
+static double sq_diff(double x, double y){ return (x-y)*(x-y); }
 
-// Checks whether inverse gives us the data back
-// NOTE: modifies the global seq_result
-static void check_inverse(double threshold){
-	for(unsigned int i = 0; i < ITERS; ++i){
-		wvlt::unwavelet(seq_result.data(), seq_result.size(), 1);
+static void compare_results(std::vector<double> const & lh, std::vector<double> const & rh, double threshold){
+	if(lh == rh){
+		std::cout << colors::green("SUCCES:") << " bitwise qual" << std::endl;
+		return;
 	}
-	bool same = true;
-	for(unsigned int i = 0; i < N; ++i){
-		if(data(i) != seq_result[i]) same = false;
-		auto sq = data(i) - seq_result[i];
-		seq_result[i] = sq*sq;
-	}
-	auto rmse = std::sqrt(std::accumulate(seq_result.begin(), seq_result.end(), 0.0) / N);
-	if(same){
-		std::cout << colors::green("SUCCES:") << " Inverse is bitwise correct" << std::endl;
+
+	double rmse = std::sqrt(std::inner_product(lh.begin(), lh.end(), rh.begin(), 0.0, std::plus<double>(), &sq_diff) / lh.size());
+	if(rmse <= threshold){
+		std::cout << colors::green("SUCCES:") << " error within threshold, rmse = " << rmse << std::endl;
 	} else {
-		if(rmse <= threshold){
-			std::cout << colors::green("SUCCES:") << " Inverse is almost correct: rmse = " << rmse << std::endl;
-		} else {
-			std::cout << colors::red("FAIL:") << " Inverse seems wrong: rmse = " << rmse << std::endl;
-		}
+		std::cout << colors::red("FAIL:") << " error to big, rmse = " << rmse << std::endl;
 	}
 }
 
@@ -152,8 +126,9 @@ int main(int argc, char** argv){
 	opts.add_options()
 		("p", po::value<unsigned int>(), "number of processors")
 		("n", po::value<unsigned int>(), "number of elements")
+		("iterations", po::value<unsigned int>()->default_value(5), "number of iterations")
 		("help", po::value<bool>(), "show this help")
-		("check", po::value(&should_check), "enables correctness checks");
+		("check", po::value<bool>(), "enables correctness checks");
 	po::variables_map vm;
 
 	// Parse and set options
@@ -169,6 +144,7 @@ int main(int argc, char** argv){
 
 		N = vm["n"].as<unsigned int>();
 		P = vm["p"].as<unsigned int>();
+		ITERS = vm["iterations"].as<unsigned int>();
 
 		if(!is_pow_of_two(N)) throw po::error("n is not a power of two");
 		if(!is_pow_of_two(P)) throw po::error("p is not a power of two");
@@ -190,7 +166,13 @@ int main(int argc, char** argv){
 	// Checking equality of algorithms
 	if(vm.count("check")){
 		double threshold = 1.0e-8;
-		check_equality(threshold);
-		check_inverse(threshold);
+		std::cout << "Checking results ";
+		compare_results(seq_result, par_result, threshold);
+
+		for(int i = 0; i < ITERS; ++i) wvlt::unwavelet(seq_result.data(), seq_result.size(), 1);
+		for(unsigned int i = 0; i < par_result.size(); ++i) par_result[i] = data(i);
+
+		std::cout << "Checking inverse ";
+		compare_results(seq_result, par_result, threshold);
 	}
 }