hetri2#

Functions

void chetri2(
    const char*          uplo,
    const INT            n,
          c64*  restrict A,
    const INT            lda,
    const INT*  restrict ipiv,
          c64*  restrict work,
    const INT            lwork,
          INT*           info
);
void chetri2(const char *uplo, const INT n, c64 *restrict A, const INT lda, const INT *restrict ipiv, c64 *restrict work, const INT lwork, INT *info)#

CHETRI2 computes the inverse of a COMPLEX*16 hermitian indefinite matrix A using the factorization A = U*D*U**T or A = L*D*L**T computed by CHETRF.

CHETRI2 sets the LEADING DIMENSION of the workspace before calling CHETRI2X that actually computes the inverse.

Parameters

in
uplo

  • 'U': Upper triangular, form is A = U*D*U**T

  • 'L': Lower triangular, form is A = L*D*L**T

in
n

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

inout
A

Array of dimension (lda,n). On entry, the block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by chetrf. On exit, if info=0, the (symmetric) inverse of the original matrix. If uplo='U', the upper triangular part of the inverse is formed and the part of A below the diagonal is not referenced; if uplo='L' the lower triangular part of the inverse is formed and the part of A above the diagonal is not referenced.

in
lda

The leading dimension of the array A. lda>=max(1,n).

in
ipiv

Array of dimension n. Details of the interchanges and the block structure of D as determined by chetrf.

out
work

Array of dimension max(1,lwork).

in
lwork

The dimension of the array work. If n=0, lwork>=1, else lwork>=(n+nb+1)*(nb+3). If lwork=-1, then a workspace query is assumed; the routine calculates the optimal size of the work array, returns this value as the first entry of the work array, and no error message related to lwork is issued.

out
info

  • info=0: successful exit

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

  • info>0: if info=i, D(i,i)=0; the matrix is singular and its inverse could not be computed.

Functions

void zhetri2(
    const char*          uplo,
    const INT            n,
          c128* restrict A,
    const INT            lda,
    const INT*  restrict ipiv,
          c128* restrict work,
    const INT            lwork,
          INT*           info
);
void zhetri2(const char *uplo, const INT n, c128 *restrict A, const INT lda, const INT *restrict ipiv, c128 *restrict work, const INT lwork, INT *info)#

ZHETRI2 computes the inverse of a COMPLEX*16 hermitian indefinite matrix A using the factorization A = U*D*U**T or A = L*D*L**T computed by ZHETRF.

ZHETRI2 sets the LEADING DIMENSION of the workspace before calling ZHETRI2X that actually computes the inverse.

Parameters

in
uplo

  • 'U': Upper triangular, form is A = U*D*U**T

  • 'L': Lower triangular, form is A = L*D*L**T

in
n

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

inout
A

Array of dimension (lda,n). On entry, the block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by zhetrf. On exit, if info=0, the (symmetric) inverse of the original matrix. If uplo='U', the upper triangular part of the inverse is formed and the part of A below the diagonal is not referenced; if uplo='L' the lower triangular part of the inverse is formed and the part of A above the diagonal is not referenced.

in
lda

The leading dimension of the array A. lda>=max(1,n).

in
ipiv

Array of dimension n. Details of the interchanges and the block structure of D as determined by zhetrf.

out
work

Array of dimension max(1,lwork).

in
lwork

The dimension of the array work. If n=0, lwork>=1, else lwork>=(n+nb+1)*(nb+3). If lwork=-1, then a workspace query is assumed; the routine calculates the optimal size of the work array, returns this value as the first entry of the work array, and no error message related to lwork is issued.

out
info

  • info=0: successful exit

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

  • info>0: if info=i, D(i,i)=0; the matrix is singular and its inverse could not be computed.