dgetri - compute the inverse of a matrix using the LU factorization computed by DGETRF
SUBROUTINE DGETRI(N, A, LDA, IPIVOT, WORK, LDWORK, INFO) INTEGER N, LDA, LDWORK, INFO INTEGER IPIVOT(*) DOUBLE PRECISION A(LDA,*), WORK(*) SUBROUTINE DGETRI_64(N, A, LDA, IPIVOT, WORK, LDWORK, INFO) INTEGER*8 N, LDA, LDWORK, INFO INTEGER*8 IPIVOT(*) DOUBLE PRECISION A(LDA,*), WORK(*) F95 INTERFACE SUBROUTINE GETRI(N, A, LDA, IPIVOT, WORK, LDWORK, INFO) INTEGER :: N, LDA, LDWORK, INFO INTEGER, DIMENSION(:) :: IPIVOT REAL(8), DIMENSION(:) :: WORK REAL(8), DIMENSION(:,:) :: A SUBROUTINE GETRI_64(N, A, LDA, IPIVOT, WORK, LDWORK, INFO) INTEGER(8) :: N, LDA, LDWORK, INFO INTEGER(8), DIMENSION(:) :: IPIVOT REAL(8), DIMENSION(:) :: WORK REAL(8), DIMENSION(:,:) :: A C INTERFACE #include <sunperf.h> void dgetri(int n, double *a, int lda, int *ipivot, int *info); void dgetri_64(long n, double *a, long lda, long *ipivot, long *info);
Oracle Solaris Studio Performance Library dgetri(3P) NAME dgetri - compute the inverse of a matrix using the LU factorization computed by DGETRF SYNOPSIS SUBROUTINE DGETRI(N, A, LDA, IPIVOT, WORK, LDWORK, INFO) INTEGER N, LDA, LDWORK, INFO INTEGER IPIVOT(*) DOUBLE PRECISION A(LDA,*), WORK(*) SUBROUTINE DGETRI_64(N, A, LDA, IPIVOT, WORK, LDWORK, INFO) INTEGER*8 N, LDA, LDWORK, INFO INTEGER*8 IPIVOT(*) DOUBLE PRECISION A(LDA,*), WORK(*) F95 INTERFACE SUBROUTINE GETRI(N, A, LDA, IPIVOT, WORK, LDWORK, INFO) INTEGER :: N, LDA, LDWORK, INFO INTEGER, DIMENSION(:) :: IPIVOT REAL(8), DIMENSION(:) :: WORK REAL(8), DIMENSION(:,:) :: A SUBROUTINE GETRI_64(N, A, LDA, IPIVOT, WORK, LDWORK, INFO) INTEGER(8) :: N, LDA, LDWORK, INFO INTEGER(8), DIMENSION(:) :: IPIVOT REAL(8), DIMENSION(:) :: WORK REAL(8), DIMENSION(:,:) :: A C INTERFACE #include <sunperf.h> void dgetri(int n, double *a, int lda, int *ipivot, int *info); void dgetri_64(long n, double *a, long lda, long *ipivot, long *info); PURPOSE dgetri computes the inverse of a matrix using the LU factorization com- puted by DGETRF. This method inverts U and then computes inv(A) by solving the system inv(A)*L = inv(U) for inv(A). ARGUMENTS N (input) The order of the matrix A. N >= 0. A (input/output) On entry, the factors L and U from the factorization A = P*L*U as computed by DGETRF. On exit, if INFO = 0, the inverse of the original matrix A. LDA (input) The leading dimension of the array A. LDA >= max(1,N). IPIVOT (input) The pivot indices from DGETRF; for 1<=i<=N, row i of the matrix was interchanged with row IPIVOT(i). WORK (workspace) On exit, if INFO=0, then WORK(1) returns the optimal LDWORK. LDWORK (input) The dimension of the array WORK. LDWORK >= max(1,N). For optimal performance LDWORK >= N*NB, where NB is the optimal blocksize returned by ILAENV. If LDWORK = -1, then a workspace query is assumed; the rou- tine only 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 LDWORK is issued by XERBLA. INFO (output) = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value > 0: if INFO = i, U(i,i) is exactly zero; the matrix is sin- gular and its inverse could not be computed. 7 Nov 2015 dgetri(3P)