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sgetri.f(3)                         LAPACK                         sgetri.f(3)

NAME
       sgetri.f -

SYNOPSIS
   Functions/Subroutines
       subroutine sgetri (N, A, LDA, IPIV, WORK, LWORK, INFO)
           SGETRI

Function/Subroutine Documentation
   subroutine sgetri (integerN, real, dimension( lda, * )A, integerLDA,
       integer, dimension( * )IPIV, real, dimension( * )WORK, integerLWORK,
       integerINFO)
       SGETRI

       Purpose:

            SGETRI computes the inverse of a matrix using the LU factorization
            computed by SGETRF.

            This method inverts U and then computes inv(A) by solving the system
            inv(A)*L = inv(U) for inv(A).

       Parameters:
           N

                     N is INTEGER
                     The order of the matrix A.  N >= 0.

           A

                     A is REAL array, dimension (LDA,N)
                     On entry, the factors L and U from the factorization
                     A = P*L*U as computed by SGETRF.
                     On exit, if INFO = 0, the inverse of the original matrix A.

           LDA

                     LDA is INTEGER
                     The leading dimension of the array A.  LDA >= max(1,N).

           IPIV

                     IPIV is INTEGER array, dimension (N)
                     The pivot indices from SGETRF; for 1<=i<=N, row i of the
                     matrix was interchanged with row IPIV(i).

           WORK

                     WORK is REAL array, dimension (MAX(1,LWORK))
                     On exit, if INFO=0, then WORK(1) returns the optimal LWORK.

           LWORK

                     LWORK is INTEGER
                     The dimension of the array WORK.  LWORK >= max(1,N).
                     For optimal performance LWORK >= 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

                     INFO is INTEGER
                     = 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
                           singular and its inverse could not be computed.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           November 2011

       Definition at line 115 of file sgetri.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2                   Sat Nov 16 2013                    sgetri.f(3)