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Variable not being asigned well

ushu (2)
Hi, I am kind of new in c++, all the problems I encountere I tried to solve them by reading webpages and posts in this forum, but I haven't been able to solve this problem. In "void solveBetaY" where there are a lot of couts we can see that the first cout shows the valors of a,b,c and d. The next cout should show the same valor as d, as it is a copy and paste, but strangely it doesn't show the same valor.

The valor of d should be the same for each j, but it isnt, it seems that the valor is not being assigned well. How can I solve this?

Thank you for your help

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  #include "stdafx.h"
#include <iostream>
#include <math.h>
using namespace std;


const double mu = 0.00002094;         //kind of nice
const double Wo = 0.032;            //kind of nice
const double Wf = 0.1;                //kind of nice
const double Wp = 109.0 / 3750.0;             //kind of nice
const double Wn = 0.028;                //kind of nice
const double Q = 4.82*pow(10, 7);        //kind of nice
const double L = 318000.0;               //kind of nice
const double cpf = 1;
const double cpo = 1;
const double cpp = 1;
const double cpn = 1;
const double Tref = 600.0;
const double Ts = 371.5;
const int nodesx = 1;
const int nodesy = 10;
const int timesteps = 2;
const int buclesmax = 2;
const double deltax = 0.00001;
const double deltay = 0.00001;
const double deltat = 0.0000001;
double ro[nodesx + 2][nodesy + 2][timesteps + 1];
double u[nodesx + 2][nodesy + 2][timesteps + 1];
double v[nodesx + 2][nodesy + 2][timesteps + 1];
double P[nodesx + 2][nodesy + 2][timesteps + 1];
double Yf[nodesx + 2][nodesy + 2][timesteps + 1];
double Yn[nodesx + 2][nodesy + 2][timesteps + 1];
double alpha[nodesx + 2][nodesy + 2][timesteps + 1];
double beta[nodesx + 2][nodesy + 2][timesteps + 1];
double a[nodesx + 2];
double b[nodesx + 2];
double c[nodesx + 2];
double d[nodesx + 2];

void TDMAy(double(&phi)[nodesx + 2][nodesy + 2][timesteps + 1], double a[nodesy], double b[nodesy], double c[nodesy], double d[nodesy], int x, int t){

	double e[nodesy + 1];
	double f[nodesy + 2];

	e[0] = c[0] / b[0];
	f[0] = d[0] / b[0];

	for (int i = 1; i<nodesy + 1; i++){
		e[i] = c[i] / (b[i] - e[i - 1] * a[i]);
		f[i] = (d[i] - f[i - 1] * a[i]) / (b[i] - e[i - 1] * a[i]);
	}

	f[nodesy + 1] = (d[nodesy + 1] - f[nodesy] * a[nodesy + 1]) / (b[nodesy + 1] - e[nodesy] * a[nodesy + 1]);

	phi[x][nodesy + 1][t] = f[nodesy + 1];
	//cout << phi[x][nodesy + 1][t] << endl;
	/*if (phi == v){
	cout << phi[x][nodesy + 1][t] << endl;
	cout << "a = " << a[nodesy + 1] << " b = " << b[nodesy + 1] << " c = " << c[nodesy + 1] << " d = " << d[nodesy + 1] << endl << endl;
	cout << "flag " << flag[nodesy+1] << endl;
	}*/

	for (int i = nodesy; i >= 0; i--){
		phi[x][i][t] = f[i] - e[i] * phi[x][i + 1][t];
		//cout << phi[x][i][t] << endl;
		/*if (phi == v){
		cout << "[" << x << "][" << i << "][" << t << "] " << phi[x][i][t] << endl;
		cout << "a = " << a[i] << " b = " << b[i] << " c = " << c[i] << " d = " << d[i] << endl ;
		cout << "flag " << flag[i] << endl<<endl;
		}*/
	}
	//cout << endl << endl << "estoy en el TDMAy" << endl << endl;
	//if (phi == v){ system("pause"); }
	return;
}

void solveBetaY(int i, int ts){
	b[0] = 1;
	c[0] = 0;
	d[0] = 1;
	b[nodesx + 1] = 1;
	a[nodesx + 1] = 0;
	d[nodesx + 1] = 1;
	for (int j = 1; j < nodesy + 1; j++){

		if (u[i][j][ts] >= 0 && v[i][j][ts] >= 0){

			a[j] = -(ro[i][j - 1][ts] * v[i][j - 1][ts] / deltay) - (mu) / (deltay*deltay);


			b[j] = (ro[i][j][ts] / deltat) + (ro[i][j][ts] * v[i][j][ts] / deltay) + (2 * mu) / (deltay*deltay) + (ro[i][j][ts] * u[i][j][ts] / deltax) + (2 * mu) / (deltax*deltax);


			c[j] = -(mu) / (deltay*deltay);


			d[i] = (ro[i][j][ts - 1] * beta[i][j][ts - 1] / deltat) + (ro[i - 1][j][ts] * u[i - 1][j][ts] * beta[i - 1][j][ts] / deltax) + mu*(beta[i + 1][j][ts] + beta[i - 1][j][ts]) / (deltax*deltax) + (P[i][j][ts] - P[i][j][ts - 1]) / (deltat) +(mu / 3)* ((u[i + 1][j][ts] * u[i + 1][j][ts] + u[i - 1][j][ts] * u[i - 1][j][ts] - 2 * u[i][j][ts] * u[i][j][ts]) / (deltax*deltax) + (v[i][j + 1][ts] * v[i][j + 1][ts] + v[i][j - 1][ts] * v[i][j - 1][ts] - 2 * v[i][j][ts] * v[i][j][ts]) / (deltay*deltay) + (u[i + 1][j][ts] * (v[i + 1][j + 1][ts] - v[i + 1][j - 1][ts]) + v[i + 1][j][ts] * (u[i + 1][j + 1][ts] - u[i + 1][j - 1][ts]) - u[i - 1][j][ts] * (v[i - 1][j + 1][ts] - v[i - 1][j - 1][ts]) - v[i - 1][j][ts] * (u[i - 1][j + 1][ts] - u[i - 1][j - 1][ts])) / (4 * deltax*deltay)) + (5 * mu / 3)*((u[i][j + 1][ts] - u[i][j - 1][ts])*(v[i + 1][j][ts] - v[1 - 1][j][ts]) / (4 * deltax*deltay) - (u[i + 1][j][ts] - u[i - 1][j][ts])*(v[i][j + 1][ts] - v[i][j - 1][ts]) / (4 * deltax*deltay));
			cout << "a [" << j << "= " << a[j] << endl << "b [" << j << "= " << b[j] << endl << "c [" << j << "= " << c[j] << endl << "d [" << j << "= " << d[j] << endl;
			cout << (ro[i][j][ts - 1] * beta[i][j][ts - 1] / deltat) + (ro[i - 1][j][ts] * u[i - 1][j][ts] * beta[i - 1][j][ts] / deltax) + mu*(beta[i + 1][j][ts] + beta[i - 1][j][ts]) / (deltax*deltax) + (P[i][j][ts] - P[i][j][ts - 1]) / (deltat)+(mu / 3)* ((u[i + 1][j][ts] * u[i + 1][j][ts] + u[i - 1][j][ts] * u[i - 1][j][ts] - 2 * u[i][j][ts] * u[i][j][ts]) / (deltax*deltax) + (v[i][j + 1][ts] * v[i][j + 1][ts] + v[i][j - 1][ts] * v[i][j - 1][ts] - 2 * v[i][j][ts] * v[i][j][ts]) / (deltay*deltay) + (u[i + 1][j][ts] * (v[i + 1][j + 1][ts] - v[i + 1][j - 1][ts]) + v[i + 1][j][ts] * (u[i + 1][j + 1][ts] - u[i + 1][j - 1][ts]) - u[i - 1][j][ts] * (v[i - 1][j + 1][ts] - v[i - 1][j - 1][ts]) - v[i - 1][j][ts] * (u[i - 1][j + 1][ts] - u[i - 1][j - 1][ts])) / (4 * deltax*deltay)) + (5 * mu / 3)*((u[i][j + 1][ts] - u[i][j - 1][ts])*(v[i + 1][j][ts] - v[1 - 1][j][ts]) / (4 * deltax*deltay) - (u[i + 1][j][ts] - u[i - 1][j][ts])*(v[i][j + 1][ts] - v[i][j - 1][ts]) / (4 * deltax*deltay)) << endl;
			cout << endl << (ro[i][j][ts - 1] * beta[i][j][ts - 1] / deltat) << endl;
			cout << endl << (ro[i - 1][j][ts] * u[i - 1][j][ts] * beta[i - 1][j][ts] / deltax) << endl;
			cout << endl << mu*(beta[i + 1][j][ts] + beta[i - 1][j][ts]) / (deltax*deltax) << endl;
			cout << endl << (P[i][j][ts] - P[i][j][ts - 1]) / (deltat) << endl;
			cout << endl << (mu / 3)* ((u[i + 1][j][ts] * u[i + 1][j][ts] + u[i - 1][j][ts] * u[i - 1][j][ts] - 2 * u[i][j][ts] * u[i][j][ts]) / (deltax*deltax) + (v[i][j + 1][ts] * v[i][j + 1][ts] + v[i][j - 1][ts] * v[i][j - 1][ts] - 2 * v[i][j][ts] * v[i][j][ts]) / (deltay*deltay) + (u[i + 1][j][ts] * (v[i + 1][j + 1][ts] - v[i + 1][j - 1][ts]) + v[i + 1][j][ts] * (u[i + 1][j + 1][ts] - u[i + 1][j - 1][ts]) - u[i - 1][j][ts] * (v[i - 1][j + 1][ts] - v[i - 1][j - 1][ts]) - v[i - 1][j][ts] * (u[i - 1][j + 1][ts] - u[i - 1][j - 1][ts])) / (4 * deltax*deltay)) + (5 * mu / 3)*((u[i][j + 1][ts] - u[i][j - 1][ts])*(v[i + 1][j][ts] - v[1 - 1][j][ts]) / (4 * deltax*deltay) - (u[i + 1][j][ts] - u[i - 1][j][ts])*(v[i][j + 1][ts] - v[i][j - 1][ts]) / (4 * deltax*deltay)) << endl;
			system("pause");
		}
		
		else {

			a[j] = 0;


			b[j] = 0;


			c[j] = 0;


			d[i] = 0;
		}

	}

	TDMAy(beta, a, b, c, d, i, ts);
	return;
}

int _tmain(int argc, _TCHAR* argv[])
{
	for (int i = 0; i < nodesx + 2; i++){    //condicions inicials
		for (int y = 0; y < nodesy + 2; y++){
			for (int t = 0; t < timesteps + 1; t++){
				u[i][y][t] = 1;
				v[i][y][t] = 1;
				P[i][y][t] = 100000;

				Yf[i][y][t] = 0;   //1
				Yn[i][y][t] = 329.0 / 429.0;
				alpha[i][y][t] = -vr * (100.0 / 429.0);


				beta[i][y][t] = 1; 

				ro[i][y][t] = 1;
				
			}			
		}
	}
	solveBetaY(1, 1);
	for (int i = 0; i < nodesy + 2; i++){
		cout << beta[1][i][1] << endl;
	}
	system("pause");
}
cire (8284)
The valor of d should be the same for each j,

You don't assign anything to d[j]. On the other hand, you do assign to d[i] on lines 97 and 119.

(By the way, it is value, not valor.)
ushu (2)
Thanks a lot for your help, I can't believe the error was s stupid, hours of checking for this hahahaha.

Thank you very much again! I apreciate it a lot :D
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