1STRTRI(1)                LAPACK routine (version 3.1)                STRTRI(1)
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NAME

6       STRTRI - the inverse of a real upper or lower triangular matrix A
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SYNOPSIS

9       SUBROUTINE STRTRI( UPLO, DIAG, N, A, LDA, INFO )
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11           CHARACTER      DIAG, UPLO
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13           INTEGER        INFO, LDA, N
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15           REAL           A( LDA, * )
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PURPOSE

18       STRTRI  computes the inverse of a real upper or lower triangular matrix
19       A.
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21       This is the Level 3 BLAS version of the algorithm.
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ARGUMENTS

25       UPLO    (input) CHARACTER*1
26               = 'U':  A is upper triangular;
27               = 'L':  A is lower triangular.
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29       DIAG    (input) CHARACTER*1
30               = 'N':  A is non-unit triangular;
31               = 'U':  A is unit triangular.
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33       N       (input) INTEGER
34               The order of the matrix A.  N >= 0.
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36       A       (input/output) REAL array, dimension (LDA,N)
37               On entry, the triangular matrix A.  If UPLO = 'U', the  leading
38               N-by-N  upper triangular part of the array A contains the upper
39               triangular matrix, and the strictly lower triangular part of  A
40               is  not  referenced.   If  UPLO = 'L', the leading N-by-N lower
41               triangular part of the array A contains  the  lower  triangular
42               matrix, and the strictly upper triangular part of A is not ref‐
43               erenced.  If DIAG = 'U', the diagonal elements of  A  are  also
44               not referenced and are assumed to be 1.  On exit, the (triangu‐
45               lar) inverse of the original matrix, in the same  storage  for‐
46               mat.
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48       LDA     (input) INTEGER
49               The leading dimension of the array A.  LDA >= max(1,N).
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51       INFO    (output) INTEGER
52               = 0: successful exit
53               < 0: if INFO = -i, the i-th argument had an illegal value
54               >  0:  if  INFO  =  i,  A(i,i) is exactly zero.  The triangular
55               matrix is singular and its inverse can not be computed.
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59 LAPACK routine (version 3.1)    November 2006                       STRTRI(1)
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