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initialize a matrix in while-loop

zizigooloo (3)
Hi,
I have written a program, in which I create a NxN-matrix.
As I need some different samples (some different such NxN-matrices), I try to create a new matrix in each recall of a while-loop. The first recall of the while-loop works without any problems, but the second recall crashes, but I get any errors from the compiler.
Here is my quell code. The problem should be with line 44: 
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#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <math.h>
#include <iostream>
#include <ctype.h>
#include <string>
#include <iostream>
#include <fstream>
using namespace std;
int main(){
	int N=10;
	int timeStep=10;
	string species;
	string matrix[N][N];
	int samples = 10; // repeating simulation and making an average over different samples
	int numberOfOutputs = 6; //	 The outputs are: AA_density	AB_density	BB_density	AA_AB	AA_BB	AB_BB
	double averageMaker[timeStep][numberOfOutputs];
	/* initialize the elements of averageMaker to zero */
	for(int i=0; i<timeStep; i++){
		for(int j=0; j< numberOfOutputs; j++){
			averageMaker[i][j]= 0;
		}
	}

	srand(time(NULL));
	double speciesAA, speciesBB, speciesAB; // number of species
	double AA_density, AB_density, BB_density;
	while(samples!=0){
		speciesAA=0; speciesBB=0; speciesAB=0; // number of species
		/*initialize the lattice and counting the number of different species*/
		for(int i=0; i<N; i++){
			for(int j=0; j<N; j++){
				int r = rand()%2;
				if(r==0){
					species = "AA";
					speciesAA = speciesAA + 1;
				}
				else{
					species = "BB";
					speciesBB = speciesBB + 1;
				}
				matrix[i][j]=species;
				cout<<"Here is the Problem !!!"<<endl;
			}
		}

		/*density of each species*/
		AA_density = speciesAA/(N*N);
		AB_density = speciesAB/(N*N);
		BB_density = speciesBB/(N*N);

			averageMaker[0][0] = averageMaker[0][0] + AA_density;
			averageMaker[0][1] = averageMaker[0][1] + AB_density;
			averageMaker[0][2] = averageMaker[0][2] + BB_density;
			averageMaker[0][3] = averageMaker[0][3] + 1;
			averageMaker[0][4] = averageMaker[0][4] + 1;
			averageMaker[0][5] = averageMaker[0][5] + 1;

			for(int i=1; i<=timeStep; i++){ // Monte Carlo timeStep
				for(int l=0; l<N*N; l++){//in each timeStep we have N*N updates
					std::string site = "CC" ;
					std::string neighbour = "CC";
					/*choosing a site randomly*/
					int siteRow = rand()%N;
					int siteColumn = rand()%N;
					site = matrix[siteRow][siteColumn];
					/*choosing a neighbor randomly for periodic boundary condition */
					int rowOrColumn = rand()%2;
					int moreOrLess = rand()%2;
					if(rowOrColumn == 0){ //changing row
						if(moreOrLess == 0 && siteRow != N-1)
							neighbour= matrix[siteRow + 1][siteColumn]; //choosing lower neighbour
						if(moreOrLess == 1 && siteRow != 0)
							neighbour= matrix[siteRow - 1][siteColumn]; //choosing upper neighbour
						// if the site is a border-site:
						if(moreOrLess == 0 && siteRow == N-1)
							neighbour= matrix[0][siteColumn];
						if(moreOrLess == 1 && siteRow == 0)
							neighbour= matrix[N-1][siteColumn];
					}
					else{ //choosing column
						if(moreOrLess == 0 && siteColumn != N-1)	neighbour= matrix[siteRow][siteColumn + 1]; //choosing right hand side neighbour
						if(moreOrLess == 1 && siteColumn != 0)	neighbour= matrix[siteRow][siteColumn - 1]; //choosing left hand side neighbour
						// if the site is a border-site:
						if(moreOrLess == 0 && siteColumn == N-1)	neighbour= matrix[siteRow][0];
						if(moreOrLess == 1 && siteColumn == 0)	neighbour= matrix[siteRow][N - 1];
					}

					/* defining site's neighbors */
					std::string siteNeighbor_up, siteNeighbor_down, siteNeighbor_left, siteNeighbor_right;
					int upSite, downSite, leftSite, rightSite;
					upSite = siteRow -1;
					if(upSite == -1) upSite = N-1;
					downSite = siteRow +1;
					if(downSite == N) downSite = 0;
					leftSite = siteColumn -1;
					if(leftSite == -1) leftSite = N-1;
					rightSite = siteColumn +1;
					if(rightSite == N) rightSite = 0;
					siteNeighbor_up = matrix[upSite][siteColumn];
					siteNeighbor_down = matrix[downSite][siteColumn];
					siteNeighbor_left = matrix[siteRow][leftSite];
					siteNeighbor_right = matrix[siteRow][rightSite];

					
					/*interaction*/
					if((site == "AA" && neighbour == "BB") || (site == "BB" && neighbour == "AA")){
						matrix[siteRow][siteColumn] = "AB";
						speciesAB = speciesAB + 1;
						if(site == "AA") speciesAA = speciesAA - 1; // number of species
						else speciesBB = speciesBB - 1;
					}
					if((site == "AA" && neighbour == "AB") || (site == "AB" && neighbour == "AA")){
						matrix[siteRow][siteColumn] = "AA";
						if(site == "AB"){
							speciesAA = speciesAA + 1;
							speciesAB = speciesAB - 1;
						}
					}
					if((site == "AB" && neighbour == "BB") || (site == "BB" && neighbour == "AB")){
						matrix[siteRow][siteColumn] = "BB";
						if(site == "AB"){
							speciesBB = speciesBB + 1;
							speciesAB = speciesAB - 1;
						}
					}

					
				}
				/*density of each species*/
				AA_density = speciesAA/(N*N);
				AB_density = speciesAB/(N*N);
				BB_density = speciesBB/(N*N);

				averageMaker[i][0] = averageMaker[i][0] + AA_density;
				averageMaker[i][1] = averageMaker[i][1] + AB_density;
				averageMaker[i][2] = averageMaker[i][2] + BB_density;
				averageMaker[i][3] = averageMaker[i][3] + 1;
				averageMaker[i][4] = averageMaker[i][4] + 1;
				averageMaker[i][5] = averageMaker[i][5] + 1;
			}
			samples = samples -1;
	}
}

I will be very thankful, if you could help me.
Last edited on
Null (956)
Line 60: for(int i=1; i<=timeStep; i++). I think it should be for(int i=0; i<timeStep; i++). When i==timeStep the array index is out of bounds on line 136-141
zizigooloo (3)
I changed for(int i=1; i<=timeStep; i++) to for(int i=1; i<timeStep; i++) and now it works :-) Thanks alot :-)
ar2007 (210)
the loop,
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 while (sample! = 0)

is a condition always true, because you have put 

 
 
int sample = 10;


for it never stops, and there is no other means to get out.

Line 60: for(int i=1; i<=timeStep; i++). I think it should be for(int i=0; i<timeStep; i++). When i==timeStep the array index is out of bounds on line 136-141

only with this change does not work
Last edited on
zizigooloo (3)
while (samples! = 0) is not always true, because I change the value of samples each time by samples = samples -1; in line 143.
ar2007 (210)
int N= 10;

apologizes. the long code, I hid the bottom.
however, "N" can not be a variable. must be constant.

made the change, the code works.
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