/* tminv.c CCMATH mathematics library source code.
*
* Copyright (C) 2000 Daniel A. Atkinson All rights reserved.
* This code may be redistributed under the terms of the GNU library
* public license (LGPL). ( See the lgpl.license file for details.)
* ------------------------------------------------------------------------
*/
/*
Test: minv
Uses: mmul mcopy matprt
Input data file: mat.dat
*/
#include "ccmath.h"
void main(int na,char **av)
{ int i,n; FILE *fp;
double *p,*a,*b,*c;
if(na!=2){ printf("para: input_file\n"); exit(-1);}
fp=fopen(*++av,"r");
fscanf(fp,"%d",&n);
a=(double *)calloc(3*n*n,sizeof(double));
b=a+n*n; c=b+n*n;
for(i=0,p=a; i<n*n ;++i) fscanf(fp,"%lf",p++);
printf("Test of Matrix Inverse\n");
printf(" input matrix A:\n"); matprt(a,n,n,"%10f ");
mcopy(b,a,n*n);
/* invert a general real matrix */
i=minv(a,n);
if(i) printf( "singular matrix\n");
else{
printf(" inverse matrix:\n"); matprt(a,n,n,"%10f ");
mmul(c,a,b,n);
printf(" product C=inverse*A:\n"); matprt(c,n,n,"%12.9f ");
}
}
/* Test output
Test of Matrix Inverse
input matrix A:
6.000000 3.000000 1.000000 2.000000
3.000000 5.000000 2.000000 -1.000000
1.000000 2.000000 3.000000 -2.000000
2.000000 -1.000000 -2.000000 4.000000
inverse matrix:
0.527273 -0.290909 -0.309091 -0.490909
-0.290909 0.436364 -0.036364 0.236364
-0.309091 -0.036364 0.836364 0.563636
-0.490909 0.236364 0.563636 0.836364
product C=inverse*A:
1.000000000 -0.000000000 0.000000000 -0.000000000
0.000000000 1.000000000 0.000000000 0.000000000
0.000000000 0.000000000 1.000000000 0.000000000
0.000000000 0.000000000 0.000000000 1.000000000
*/
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