DGETRIRun Method

public void Run(
	int N,
	ref double[] A,
	int offset_a,
	int LDA,
	int[] IPIV,
	int offset_ipiv,
	ref double[] WORK,
	int offset_work,
	int LWORK,
	ref int INFO
)

Public Sub Run ( 
	N As Integer,
	ByRef A As Double(),
	offset_a As Integer,
	LDA As Integer,
	IPIV As Integer(),
	offset_ipiv As Integer,
	ByRef WORK As Double(),
	offset_work As Integer,
	LWORK As Integer,
	ByRef INFO As Integer
)

Parameters

N  Int32

(input) INTEGER The order of the matrix A. N .GE. 0.

A  Double

(input/output) DOUBLE PRECISION array, dimension (LDA,N) 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.

offset_a  Int32

 

LDA  Int32

(input) INTEGER The leading dimension of the array A. LDA .GE. max(1,N).

IPIV  Int32

(input) INTEGER array, dimension (N) The pivot indices from DGETRF; for 1.LE.i.LE.N, row i of the matrix was interchanged with row IPIV(i).

offset_ipiv  Int32

 

WORK  Double

(workspace/output) DOUBLE PRECISION array, dimension (MAX(1,LWORK)) On exit, if INFO=0, then WORK(1) returns the optimal LWORK.

offset_work  Int32

 

LWORK  Int32

(input) INTEGER The dimension of the array WORK. LWORK .GE. max(1,N). For optimal performance LWORK .GE. N*NB, where NB is the optimal blocksize returned by ILAENV. If LWORK = -1, then a workspace query is assumed; the routine 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 LWORK is issued by XERBLA.

INFO  Int32

(output) INTEGER = 0: successful exit .LT. 0: if INFO = -i, the i-th argument had an illegal value .GT. 0: if INFO = i, U(i,i) is exactly zero; the matrix is singular and its inverse could not be computed.

Reference