Computing the inverse of a matrix using lapack in C

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Here is the working code for computing the inverse of a matrix using lapack in C/C++:

#include <cstdio>

extern "C" {
    // LU decomoposition of a general matrix
    void dgetrf_(int* M, int *N, double* A, int* lda, int* IPIV, int* INFO);

    // generate inverse of a matrix given its LU decomposition
    void dgetri_(int* N, double* A, int* lda, int* IPIV, double* WORK, int* lwork, int* INFO);
}

void inverse(double* A, int N)
{
    int *IPIV = new int[N];
    int LWORK = N*N;
    double *WORK = new double[LWORK];
    int INFO;

    dgetrf_(&N,&N,A,&N,IPIV,&INFO);
    dgetri_(&N,A,&N,IPIV,WORK,&LWORK,&INFO);

    delete[] IPIV;
    delete[] WORK;
}

int main(){

    double A [2*2] = {
        1,2,
        3,4
    };

    inverse(A, 2);

    printf("%f %f\n", A[0], A[1]);
    printf("%f %f\n", A[2], A[3]);

    return 0;
}

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