create NEAT app repo

Random.cpp

@@ -0,0 +1,103 @@
+#include "Random.h"
+
+#include <algorithm>
+#include <cstdarg>
+#include <cstdlib>
+
+#include "IteratorHelper.h"
+#include "NEAT.h"
+
+static float Random()
+{
+	return (float)rand() / (float)RAND_MAX;
+}
+
+float RandomFloatRange(float min, float max)
+{
+	if ( max < min )
+	{
+		std::swap(min,max);
+	}
+
+	return (Random() * (max - min)) + min;
+}
+
+float RandomWeight()
+{
+	return RandomFloatRange(-NEAT::kMaxNewWeight,NEAT::kMaxNewWeight);
+}
+
+bool RandomBool()
+{
+	return ((rand() % 2) == 0);
+}
+
+float RandomPreturbation()
+{
+	return RandomFloatRange(-NEAT::kMaxWeightPerturbation,NEAT::kMaxWeightPerturbation);
+}
+
+int RandomRange(int min, int max)
+{
+	return (rand() % (max - min + 1)) + min;
+}
+
+bool RandomChance(float pSuccess)
+{
+	return Random() <= pSuccess;
+}
+
+int RandomZeroBiased(int max)
+{
+	float fmin = (float)-max;
+	float fmax = (float)max;
+	float fsum = 0.0f;
+
+	for (int i=0;i<6;++i)
+	{
+		fsum += RandomFloatRange(fmin,fmax);
+	}
+	if ( fsum < 0.0f )
+	{
+		fsum = -fsum;
+	}
+	return (int)(fsum / 6.0f);
+}
+
+int Roulette(int n, ...)
+{
+	// store the arguments so we can use them more easily
+	va_list args;
+	va_start(args,n);
+	std::vector<float> weights;
+	iterate_times(n)
+	{
+		weights.push_back((float)va_arg(args,double));
+	}
+	va_end(args);
+	
+	// sum them
+	float sum = 0.0;
+	iterate_each(std::vector<float>::iterator, it, weights)
+	{
+		sum += (*it);
+	}
+	
+	// roll the dice
+	float roll = RandomFloatRange(0.0f, sum);
+	
+	// see where it falls
+	sum = 0.0f;
+	for( unsigned int i = 0; i < weights.size(); ++i )
+	{
+		sum += weights[i];
+		if ( roll <= sum )
+		{
+			return i;
+		}
+	}
+	
+	// failure, should not get here!
+	assert(0);
+	return -1;
+}