67 lines
1.9 KiB
C++
67 lines
1.9 KiB
C++
#include <cassert>
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#include <cstdlib>
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#include <ctime>
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#include "chain-random-walk.h"
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namespace {
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constexpr int default_size = 7;
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constexpr int default_steps = 100000000;
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constexpr int outlines = 25;
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}
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/* first argument: array size
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* second argument: number of steps
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*/
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int main(int argc, char** argv)
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{
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long size = default_size;
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if(argc > 1) size = std::atol(argv[1]);
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assert(size > 0);
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long steps = default_steps;
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if(argc > 2) steps = std::atol(argv[2]);
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assert(steps > 0);
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long outfreq = steps / outlines;
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if(outfreq < 1) outfreq = 1;
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/* the configuration is given by an array of float numbers */
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float* present_configuration = new float[size]();
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/* store the one with greatest deviation between min and max element */
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float* extreme_configuration = present_configuration;
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float extreme_elongation = 0.0;
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double el_sum = 0.0;
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double el_avg = 0.0;
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std::srand(std::time(nullptr)); // initialize the random number generator
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for(long i = 0; i < steps; i++)
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{
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if(i % outfreq == 0)
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crw::output(i, size, present_configuration, extreme_configuration, el_avg);
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/* here we are calling the random walk step;
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* this returns a new configuration (float array) on the heap
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*/
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// Simple fix to memleak:
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float* old_configuration = present_configuration;
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present_configuration = crw::step(size, present_configuration);
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delete old_configuration;
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float present_elongation = crw::elongation(size, present_configuration);
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if(present_elongation > extreme_elongation)
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{
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extreme_configuration = present_configuration;
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extreme_elongation = present_elongation;
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}
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el_sum += present_elongation;
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el_avg = el_sum / (i + 1.0);
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}
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crw::output(steps, size, present_configuration, extreme_configuration, el_avg);
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delete[] present_configuration;
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}
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