From 21a873e909e3d5937b421ca8bf90e9de1b592ee6 Mon Sep 17 00:00:00 2001
From: Joshua Moerman <lakseru@gmail.com>
Date: Mon, 26 Mar 2012 00:05:18 +0200
Subject: [PATCH] better code

---
 aatester.cpp | 32 +++++++++-----------------------
 analyse.hpp  | 29 +++++++++++++++++++++--------
 2 files changed, 30 insertions(+), 31 deletions(-)

diff --git a/aatester.cpp b/aatester.cpp
index afba8b0..fcb465c 100644
--- a/aatester.cpp
+++ b/aatester.cpp
@@ -20,24 +20,21 @@
 int verbose = 0;
 Logger logger(std::cout, LOG_VERBOSE);
 
-inline double test(const int dimension, const double doubling, const double percentage){
+inline double test(const unsigned int dimension){
 	LOG("making vector",
-	srand(time(0));
-	std::vector<double *> buffer(1000000);
+	std::vector<double *> buffer(10000000);
 	);
 	
 	LOG("making random data",
 	for(auto & p : buffer){
 		p = new double[dimension];
-		for(unsigned int i = 2;i < dimension; ++i){
+		for(unsigned int i = 0;i < dimension; ++i){
 			p[i] = rand() / (double) RAND_MAX - 0.5;
 		}
-		p[0] = p[1]*p[1];
-		p[1] = std::sin(5.0*p[2]);
 	});
 	
 	LOG("calculate fractal dimension",
-	double f = fractal_dimension(buffer.begin(), buffer.end(), dimension, doubling, percentage);
+	double f = fractal_dimension(buffer.begin(), buffer.end(), dimension);
 	);
 	
 	LOG("freeing data",
@@ -50,22 +47,11 @@ inline double test(const int dimension, const double doubling, const double perc
 }
 
 int main(){
-	double percentages[] = {0.00015, 0.00010, 0.00006, 0.00004, 0.000015};
-	std::cout << "... |";
-	for(auto p : percentages) std::cout << "\t" << p;
-	std::cout << std::endl << "----------------------------------------------" << std::endl;
-	
-	for (double doubling = 2.0; doubling <= 3.0; doubling += 0.1){
-		std::cout << doubling << " |";
-		for (auto p : percentages){
-			double sse = 0;
-			for (int i = 3; i <= 6; ++i) {
-				for(int j = 0; j < 20; ++j) {
-					double e = (i-2) - test(i, doubling, p);
-					sse += e*e;
-				}
-			}
-			std::cout << "\t" << sse;
+	srand(time(0));
+	for (unsigned int i = 1; i <= 6; ++i) {
+		std::cout << i << " =>";
+		for(unsigned int j = 0; j < 10; ++j) {
+			std::cout << "\t" << test(i);
 		}
 		std::cout << std::endl;
 	}
diff --git a/analyse.hpp b/analyse.hpp
index b56e8b3..7000430 100644
--- a/analyse.hpp
+++ b/analyse.hpp
@@ -19,29 +19,42 @@ inline double distance_squared(double * p1, double * p2, size_t dimension){
 	return s;
 }
 
+struct fractal_dimension_settings{
+	double doubling;
+	double size;
+	size_t chunk_size;
+	
+	fractal_dimension_settings()
+	: doubling(2.4)
+	, size(0.035)
+	, chunk_size(200)
+	{}
+};
+
 template <typename Iterator>
-double fractal_dimension(Iterator begin, Iterator end, size_t const dimension, const double doubling = 2.4, const double percentage = 0.00004) {
-	const double size = std::pow(percentage, 1.0 / 3.0);
-	//const double size = std::pow(percentage, 1.0 / dimension);
+double fractal_dimension(Iterator begin, Iterator end, size_t const dimension, const fractal_dimension_settings settings = fractal_dimension_settings() ) {
+	const double size = settings.size;
 	const double totalSize = std::sqrt(dimension);
 	
+	const double r1 = size * totalSize * size * totalSize;
+	const double r2 = r1 * settings.doubling * settings.doubling;
+	
 	unsigned int counts[2] = {};
-	double r = size * totalSize;
 	
 	while(begin != end){
 		auto x0 = *begin++;
 		
-		for(unsigned int i = 0; i < 200 && begin != end; ++i){
+		for(unsigned int i = 0; i < settings.chunk_size && begin != end; ++i){
 			auto x = *begin++;
 			auto d = distance_squared(x, x0, dimension);
-			if( d <= r*r )
+			if( d <= r1 )
 				++counts[0];
-			if( d <= doubling*doubling*r*r )
+			if( d <= r2 )
 				++counts[1];
 		}
 	}
 	
-	return std::log((double) counts[1] / (double) counts[0]) / std::log(doubling);
+	return std::log((double) counts[1] / (double) counts[0]) / std::log(settings.doubling);
 }
 
 #endif