1ZTRTI2(1)                LAPACK routine (version 3.1)                ZTRTI2(1)
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NAME

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

9       SUBROUTINE ZTRTI2( 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           COMPLEX*16     A( LDA, * )
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PURPOSE

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

25       UPLO    (input) CHARACTER*1
26               Specifies whether the matrix A is upper or lower triangular.  =
27               'U':  Upper triangular
28               = 'L':  Lower triangular
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30       DIAG    (input) CHARACTER*1
31               Specifies  whether  or  not the matrix A is unit triangular.  =
32               'N':  Non-unit triangular
33               = 'U':  Unit triangular
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35       N       (input) INTEGER
36               The order of the matrix A.  N >= 0.
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38       A       (input/output) COMPLEX*16 array, dimension (LDA,N)
39               On entry, the triangular matrix A.  If UPLO = 'U', the  leading
40               n  by n upper triangular part of the array A contains the upper
41               triangular matrix, and the strictly lower triangular part of  A
42               is  not  referenced.   If  UPLO = 'L', the leading n by n lower
43               triangular part of the array A contains  the  lower  triangular
44               matrix, and the strictly upper triangular part of A is not ref‐
45               erenced.  If DIAG = 'U', the diagonal elements of  A  are  also
46               not referenced and are assumed to be 1.
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48               On  exit,  the  (triangular) inverse of the original matrix, in
49               the same storage format.
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51       LDA     (input) INTEGER
52               The leading dimension of the array A.  LDA >= max(1,N).
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54       INFO    (output) INTEGER
55               = 0: successful exit
56               < 0: if INFO = -k, the k-th argument had an illegal value
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60 LAPACK routine (version 3.1)    November 2006                       ZTRTI2(1)
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