1ZTRTI2(1)                LAPACK routine (version 3.2)                ZTRTI2(1)
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NAME

6       ZTRTI2  -  computes  the inverse of a complex upper or lower triangular
7       matrix
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SYNOPSIS

10       SUBROUTINE ZTRTI2( UPLO, DIAG, N, A, LDA, INFO )
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12           CHARACTER      DIAG, UPLO
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14           INTEGER        INFO, LDA, N
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16           COMPLEX*16     A( LDA, * )
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PURPOSE

19       ZTRTI2 computes the inverse of a  complex  upper  or  lower  triangular
20       matrix.  This is the Level 2 BLAS version of the algorithm.
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ARGUMENTS

23       UPLO    (input) CHARACTER*1
24               Specifies whether the matrix A is upper or lower triangular.  =
25               'U':  Upper triangular
26               = 'L':  Lower triangular
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28       DIAG    (input) CHARACTER*1
29               Specifies whether or not the matrix A is  unit  triangular.   =
30               'N':  Non-unit triangular
31               = 'U':  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) COMPLEX*16 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 = -k, the k-th argument had an illegal value
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57 LAPACK routine (version 3.2)    November 2008                       ZTRTI2(1)
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