POTRI - 5.2 English - 68552

AOCL API Guide (68552)

Document ID
68552
Release Date
2025-12-29
Version
5.2 English
template<typename T>
void potri(char *uplo, integer *n, T *buff_A, integer *ldim_A, integer *info)#

Inverse of a real symmetric positive definite matrix.

Purpose:

    Computation of the inverse of a real symmetric positive definite matrix a using the
    Cholesky factorization A = U**T*U or A = L*L**T computed by SPOTRF.
Parameters:
  • uplo[in]

    uplo is char*

    = ‘U’: Upper triangle of a is stored;

    = ‘L’: Lower triangle of a is stored.
  • n[in]

    n is integer*

    The order of the matrix a. n >= 0.

  • a[inout]

    a is float/double/COMPLEX/COMPLEX*16 array, dimension (lda,n)

    On entry, the triangular factor U or L from the Cholesky factorization A = U**T*U or A = L*L**T, as computed by SPOTRF.

    On exit, the upper or lower triangle of the (symmetric) inverse of A, overwriting the input factor U or L.
  • lda[in]

    lda is integer*

    The leading dimension of the matrix a, lda >= fla_max(1,n)

  • INFO[out]

    INFO is INTEGER

    = 0: successful exit

    < 0: if INFO = -i, the i-th argument had an illegal value

    > 0: if INFO = i, the (i,i) element of the factor U or L is zero, and the inverse could not be computed.