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m (One dimensional stedy state conduction with Heat generation code using C)
(Removed example code; putting it in separate page.)
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#include <stdio.h>
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* [[One dimensional steady state conduction with heat generation | One dimensional steady state conduction with heat generation code in C]]
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#include <stdlib.h>
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#define MAXROWS 10000
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double **GetMatrix(double, double, double, double, double, int);
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void squareoutput(double **, int);
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void nonsquareoutput(double **, int, int);
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double **triangularize(double *[MAXROWS], int, int);
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double *returnsolvector(double **c, int nrows);
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void writeoutputvector(double *p, int nrows);
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int main(int argc, char **argv)
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{
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/*
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Variables chosen:
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GAMMA:  Thermal Conductivity
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L : Length of the domain
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Dx : Node spacing
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*/
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double GAMMA, L, Dx, Ta , Tb, Area;
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int N, row;
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double **temp;
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double **aug;
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double *solvector;
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printf("\nThis program works for only simple 1-D conduction");
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printf("Is thermal Conductivity constant?");
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printf("\nEnter the Value for Heat conductivity");
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scanf("%lf", &GAMMA);
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printf("\nEnter the Length of the computational domain");
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scanf("%lf", &L);
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printf("\nEnter the cross-sectional area of the computational domain");
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scanf("%lf", &Area);
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printf("\nEnter the temperature at the ends of the domain");
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scanf("%lf %lf", &Ta, &Tb);
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printf("\nEnter the number of Nodes u want to be chosen for analysis");
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scanf("%d", &N);
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temp=(double **) malloc(N*sizeof(double *));
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    for(row=0;row<N;row++)
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    temp[row]=(double *) malloc(N*sizeof(double));
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aug= (double **) malloc ((N+1)*sizeof(double));
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    for(row=0;row<N;row++)
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    aug[row]=(double *) malloc((N+1)*sizeof(double));
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solvector= (double *) malloc (N*sizeof(double));
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Dx=L/(N);
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printf("\nThe Node spacing is: %lf", Dx);
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aug=GetMatrix(GAMMA, Dx, Ta, Tb, Area, N);
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aug=triangularize(aug, N, N+1);
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nonsquareoutput(aug, N, N+1);
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printf("\n\n");
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solvector=returnsolvector(aug,N);
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writeoutputvector(solvector, N);
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printf("\n\n\n");
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return 0;
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}
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double **GetMatrix(double GAMMA, double Dx, double Ta, double Tb, double Area, int N)
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{
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int row, col;
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double DxW, DxE;
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double Aw, Ae, Ap;
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/* Memory Allocation for the matrix */
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double **matrix; double *solvector;
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double **aug;
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solvector= (double *) malloc (N*sizeof(double));
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matrix=(double **) malloc(N*sizeof(double));
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    for(row=0;row<N;row++)
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    matrix[row]=(double *) malloc(N*sizeof(double));
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aug= (double **) malloc ((N+1)*sizeof(double));
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    for(row=0;row<N;row++)
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    aug[row]=(double *) malloc((N+1)*sizeof(double));
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/* Uniform Mesh has been chosen */
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DxW=DxE=Dx;
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Aw=(GAMMA/DxW)*Area;
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Ae=(GAMMA/DxE)*Area;
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/* Generation of the Matrix */
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row=0;
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for(col=0; col<N; col++)
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{
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if(col==row)
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*(*(matrix+row)+col)= (Ae+2*Aw);
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else if(col==row+1)
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*(*(matrix+row)+col)= -Ae ;
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else
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*(*(matrix+row)+col)=0;
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}
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for (row=1; row<N-1; row++)
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{
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for(col=0; col<N; col++)
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{
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if(col==row+1)
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*(*(matrix+row)+col)= -Aw;
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else if (col==row-1)
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*(*(matrix+row)+col)= -Ae;
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else if (col==row)
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*(*(matrix+row)+col)= (Aw+Ae);
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else
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*(*(matrix+row)+col)=0;
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}
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}
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row=N-1;
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for(col=0; col<N; col++)
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{
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if(col==row)
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*(*(matrix+row)+col)= (2*Ae+Aw);
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else if(col==row-1)
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*(*(matrix+row)+col)=-Aw;
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else
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*(*(matrix+row)+col)=0;
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}
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/* Getting the solution vector */
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*(solvector+0)= 2*Aw*Ta;
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for (row=1; row<=N-2; row++)
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*(solvector+row)=0;
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*(solvector+N-1)= 2*Ae*Tb;
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/* Getting the augmented matrix */
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for (row=0; row<N; row++)
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{
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for(col=0; col<N; col++)
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{
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*(*(aug+row)+col) = *(*(matrix+row)+col);
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}
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}
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for (row=0; row<N; row++)
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*(*(aug+row)+N)= *(solvector+row);
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return(aug);
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}
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/* Displaying the matrix */
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void squareoutput(double **c, int nrows)
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{
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int row, col;
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for(row=0; row<nrows; row++)
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{
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printf("\n");printf("\n");
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for (col=0; col<nrows; col++)
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{
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printf("%8.2lf", *(c[row]+col));
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}
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}
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return;
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}
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void nonsquareoutput(double **c, int nrows, int ncols)
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{
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int row, col;
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for(row=0; row<nrows; row++)
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{
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printf("\n");printf("\n");
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for (col=0; col<ncols; col++)
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{
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printf("%12.2lf", *(c[row]+col));
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}
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}
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return;
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}
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double **triangularize(double *a[MAXROWS], int nrows, int ncols)
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{
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int row, col, k, temp=0;
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double coef;
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double **tri;
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tri=(double **)malloc(ncols*sizeof(double *));
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    for(row=0;row<nrows;row++)
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    tri[row]=(double*)malloc(ncols*sizeof(double));
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{
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int row, col;
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for (row=0; row<nrows; row++)
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for(col=0; col<ncols; col++)
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*(tri[row]+col)=*(a[row]+col);
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}
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for(temp=0;temp<nrows-1; temp++)
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{
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if ((tri[temp]+temp)==0)continue;
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else
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{
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for(row=temp; row<nrows; row++)
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{
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for(k=row+1; k< nrows; k++)
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{
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if( *(tri[k]+temp)==0)
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continue;
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else
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coef= (*(tri[k]+temp))/(*(tri[temp]+temp));
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for(col=0; col<ncols; col++)
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*(tri[k]+col)=*(tri[k]+col)-(coef* *(tri[row]+col));
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}
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}
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}
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}
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for(temp=nrows-1;temp>0; temp--)
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{
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if ((tri[temp]+temp)==0)continue;
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else
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{
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for(row=temp; row>0; row--)
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{
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for(k=row-1; k>=0; k--)
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{
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if( *(tri[k]+temp)==0)
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continue;
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else
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coef= (*(tri[k]+temp))/(*(tri[temp]+temp));
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for(col=0; col<ncols; col++)
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*(tri[k]+col)=*(tri[k]+col)-(coef* *(tri[row]+col));
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}
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}
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}
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}
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return(tri);
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}
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double *returnsolvector(double **c, int nrows)
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{
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int temp;
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double *solvector;
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solvector= (double *) malloc (nrows*sizeof(double));
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for(temp=0; temp<nrows; temp++)
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{
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*(solvector+temp)= *(*(c+temp)+nrows)/ *(*(c+temp)+temp);
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}
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return(solvector);
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}
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void writeoutputvector(double *p, int nrows)
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{
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int temp;
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for(temp=0; temp<nrows; temp++)
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printf("\nTemperature at Node %d = %lf", temp+1, *(p+temp));
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}
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Revision as of 08:01, 9 June 2006

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