1CPOTF2(1)                LAPACK routine (version 3.1)                CPOTF2(1)
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NAME

6       CPOTF2  -  the  Cholesky  factorization of a complex Hermitian positive
7       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.
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22       The factorization has the form
23          A = U' * U ,  if UPLO = 'U', or
24          A = L  * L',  if UPLO = 'L',
25       where U is an upper triangular matrix and L is lower triangular.
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27       This is the unblocked version of the algorithm, calling Level 2 BLAS.
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ARGUMENTS

31       UPLO    (input) CHARACTER*1
32               Specifies  whether  the  upper  or lower triangular part of the
33               Hermitian matrix A is stored.  = 'U':  Upper triangular
34               = 'L':  Lower triangular
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36       N       (input) INTEGER
37               The order of the matrix A.  N >= 0.
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39       A       (input/output) COMPLEX array, dimension (LDA,N)
40               On entry, the Hermitian matrix A.  If UPLO = 'U', the leading n
41               by  n  upper triangular part of A contains the upper triangular
42               part of the matrix A, and the strictly lower triangular part of
43               A  is  not referenced.  If UPLO = 'L', the leading n by n lower
44               triangular part of A contains the lower triangular part of  the
45               matrix  A,  and  the strictly upper triangular part of A is not
46               referenced.
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48               On exit, if INFO = 0, the factor U or L from the Cholesky  fac‐
49               torization A = U'*U  or A = L*L'.
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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
57               >  0: if INFO = k, the leading minor of order k is not positive
58               definite, and the factorization could not be completed.
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62 LAPACK routine (version 3.1)    November 2006                       CPOTF2(1)
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