在有限元等参单元计算中,大量用到Jacobi矩阵的求逆。
这里给出一个使用lapack库函数求2x2矩阵逆的例子:
/**********************************************************
File: test_lapack.c
Author: Liang Zheng
E-mail: liangzh.cug@gmail.com
Date: 2014-6-19
**********************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <lapacke.h>
int main()
{
float a[2][2]float xx[]={23.0,54.0,67.0,2.0};
lapack_int info;
int n=2;
lapack_int lda=2;
lapack_int ipiv[2]={2,2};
int i,j;
info=LAPACKE_sgetrf(LAPACK_ROW_MAJOR,n,n,a,lda,ipiv);
printf("info = %d\n",info);
for(i=0;i<2;i++)
for(j=0;j<2;j++)
printf("a= %f\n",a[i][j]);
for(i=0;i<2;i++)
printf("ipiv = %d\n",ipiv[i]);
info=LAPACKE_sgetri(LAPACK_ROW_MAJOR,n,a,lda,ipiv);
printf("info = %d\n",info);
for(i=0;i<2;i++)
for(j=0;j<2;j++)
printf("a= %f\n",a[i][j]);
return 1;
}原文地址:http://blog.csdn.net/bcboycn/article/details/32724847