1CPOTF2(1)                LAPACK routine (version 3.2)                CPOTF2(1)
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NAME

6       CPOTF2  -  computes  the  Cholesky factorization of a complex Hermitian
7       positive definite matrix A
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SYNOPSIS

10       SUBROUTINE CPOTF2( UPLO, N, A, LDA, INFO )
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12           CHARACTER      UPLO
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14           INTEGER        INFO, LDA, N
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16           COMPLEX        A( LDA, * )
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PURPOSE

19       CPOTF2 computes the Cholesky factorization of a complex Hermitian posi‐
20       tive definite matrix A.  The factorization has the form
21          A = U' * U ,  if UPLO = 'U', or
22          A = L  * L',  if UPLO = 'L',
23       where  U is an upper triangular matrix and L is lower triangular.  This
24       is the unblocked version of the algorithm, calling Level 2 BLAS.
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ARGUMENTS

27       UPLO    (input) CHARACTER*1
28               Specifies whether the upper or lower  triangular  part  of  the
29               Hermitian matrix A is stored.  = 'U':  Upper triangular
30               = 'L':  Lower triangular
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32       N       (input) INTEGER
33               The order of the matrix A.  N >= 0.
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35       A       (input/output) COMPLEX array, dimension (LDA,N)
36               On entry, the Hermitian matrix A.  If UPLO = 'U', the leading n
37               by n upper triangular part of A contains the  upper  triangular
38               part of the matrix A, and the strictly lower triangular part of
39               A is not referenced.  If UPLO = 'L', the leading n by  n  lower
40               triangular  part of A contains the lower triangular part of the
41               matrix A, and the strictly upper triangular part of  A  is  not
42               referenced.   On  exit, if INFO = 0, the factor U or L from the
43               Cholesky factorization A = U'*U  or A = L*L'.
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45       LDA     (input) INTEGER
46               The leading dimension of the array A.  LDA >= max(1,N).
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48       INFO    (output) INTEGER
49               = 0: successful exit
50               < 0: if INFO = -k, the k-th argument had an illegal value
51               > 0: if INFO = k, the leading minor of order k is not  positive
52               definite, and the factorization could not be completed.
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56 LAPACK routine (version 3.2)    November 2008                       CPOTF2(1)
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