zgbcon zgbtrf zgbtrs zgecon zgetrf zgetri zgetrs zgtcon zgttrf zgttrs zspcon zsptrf zsptri zsptrs zsycon zsytrf zsytri zsytrs

zgetri() void zgetri ( int  n, int  lda, doublecomplex  a[], int  ipiv[], doublecomplex  work[], int  lwork, int *  info  ) Inverse of a complex matrix Purpose This routine computes the inverse of a matrix using the LU factorization computed by zgetrf. This method inverts U and then computes inv(A) by solving the system inv(A)*L = inv(U) for inv(A). Parameters [in] n Order of the matrix A. (n >= 0) (If n = 0, returns without computation) [in] lda Leading dimension of the two dimensional array a[][]. (lda >= max(1, n)) [in,out] a[] Array a[la][lda] (la >= n) [in] The factors L and U from the factorization A = P*L*U as computed by zgetrf. [out] If info = 0, the inverse of the original matrix A. [in] ipiv[] Array ipiv[lipiv] (lipiv >= n) Pivot indices from zgetrf; for 1 <= i <= n, row i of the matrix was interchanged with row ipiv[i-1]. [out] work[] Array work[lwork] Work array. On exit, if info = 0, work[0] returns the optimal lwork. [in] lwork Length of array work[]. (lwork >= max(1, n)) For optimal efficiency, lwork >= n*nb, where nb is the optimal blocksize. If lwork = -1, then a workspace query is assumed. The routine only calculates the optimal size of the work array and returns the value in work[0]. [out] info = 0: Successful exit = -1: The argument n had an illegal value (n < 0) = -2: The argument lda had an illegal value (lda < max(1, n)) = -6: The argument lwork had an illegal value (lwork too small) = i > 0: The i-th diagonal element of U is exactly zero; the matrix is singular and its inverse could not be computed. Reference LAPACK