Files
cs3460-cpp/Hw3/distributions.cpp
2019-09-27 23:21:56 -07:00

110 lines
3.5 KiB
C++

//
// Created by Brady Bodily on 9/27/19.
//
#include "distributions.hpp"
std::random_device randomDevice;
std::default_random_engine randomEngine(randomDevice());
std::vector<DistributionPair>
generateUniformDistribution(std::uint32_t howMany, std::uint32_t min,
std::uint32_t max, std::uint8_t numberBins)
{
std::uniform_int_distribution<int> distribution(min, max);
auto bins = createBins(min, max, numberBins);
for (int i = 0; i < static_cast<int>(howMany); i++)
{
int number = distribution(randomEngine);
for (int j = 0; j <= numberBins; j++)
{
if (static_cast<int>(bins[j].maxValue) >= number && static_cast<int>(bins[j].minValue) <= number)
bins[j].count++;
}
}
return bins;
}
std::vector<DistributionPair>
generateNormalDistribution(std::uint32_t howMany, float mean, float stdev,
std::uint8_t numberBins)
{
int min = static_cast<int>(mean - (4 * stdev));
int max = static_cast<int>(mean + (4 * stdev) - 1);
std::normal_distribution<double> distribution(mean, stdev);
auto bins = createBins(min, max, numberBins);
for (int i = 0; i < static_cast<int>(howMany); i++)
{
double number = distribution(randomEngine);
int position =
static_cast<int>(number - min / ((max - min) / float(numberBins)));
if (position > numberBins - 1)
bins[numberBins - 1].count++;
else if (position < 0)
bins[0].count++;
else
bins[position].count++;
}
return bins;
}
std::vector<DistributionPair>
generatePoissonDistribution(std::uint32_t howMany, std::uint8_t howOften,
std::uint8_t numberBins)
{
std::poisson_distribution<int> distribution(howOften);
int min = 0;
int max = numberBins - 1;
auto bins = createBins(min, max, numberBins);
for (int i = 0; i < static_cast<int>(howMany); i++)
{
int number = distribution(randomEngine);
if (number > numberBins - 1)
bins[numberBins - 1].count++;
else if (number < 0)
bins[0].count++;
else
bins[number].count++;
}
return bins;
}
std::vector<DistributionPair> createBins(int min, int max, int binCount)
{
std::vector<DistributionPair> myVector;
int difference = static_cast<int>(float(max - min + 1) / binCount);
for (int i = 0; i < binCount; i++)
{
DistributionPair dpair((min + i) * difference,
(min + i) * difference + difference - 1);
myVector.push_back(dpair);
}
return myVector;
}
void plotDistribution(std::string title,
const std::vector<DistributionPair>& distribution,
const std::uint8_t maxPlotLineSize)
{
std::cout << title << std::endl;
auto max = 0;
for (auto currentBin : distribution)
{
if (static_cast<int>(currentBin.count) > static_cast<int>(max))
max = currentBin.count;
}
for (auto currentBin : distribution)
{
int starCount =
static_cast<int>(currentBin.count / float(max) * maxPlotLineSize);
std::string info = "[ " + std::to_string(currentBin.minValue) + ", " +
std::to_string(currentBin.maxValue) + " ] : ";
std::string starString;
for (int i = 0; i < starCount; i++)
starString += "*";
std::cout << std::setw(15) << info << starString;
std::cout << std::endl;
}
}