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

6       ZPPTRS - a system of linear equations A*X = B with a Hermitian positive
7       definite matrix A in packed storage using the Cholesky factorization  A
8       = U**H*U or A = L*L**H computed by ZPPTRF
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SYNOPSIS

11       SUBROUTINE ZPPTRS( UPLO, N, NRHS, AP, B, LDB, INFO )
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13           CHARACTER      UPLO
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15           INTEGER        INFO, LDB, N, NRHS
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17           COMPLEX*16     AP( * ), B( LDB, * )
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PURPOSE

20       ZPPTRS  solves  a  system  of linear equations A*X = B with a Hermitian
21       positive definite matrix A in packed storage using the Cholesky factor‐
22       ization A = U**H*U or A = L*L**H computed by ZPPTRF.
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ARGUMENTS

26       UPLO    (input) CHARACTER*1
27               = 'U':  Upper triangle of A is stored;
28               = 'L':  Lower triangle of A is stored.
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30       N       (input) INTEGER
31               The order of the matrix A.  N >= 0.
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33       NRHS    (input) INTEGER
34               The  number of right hand sides, i.e., the number of columns of
35               the matrix B.  NRHS >= 0.
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37       AP      (input) COMPLEX*16 array, dimension (N*(N+1)/2)
38               The triangular factor U or L from the Cholesky factorization  A
39               =  U**H*U  or  A = L*L**H, packed columnwise in a linear array.
40               The j-th column of U or L is stored in the array AP as follows:
41               if  UPLO = 'U', AP(i + (j-1)*j/2) = U(i,j) for 1<=i<=j; if UPLO
42               = 'L', AP(i + (j-1)*(2n-j)/2) = L(i,j) for j<=i<=n.
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44       B       (input/output) COMPLEX*16 array, dimension (LDB,NRHS)
45               On entry, the right hand side matrix B.  On exit, the  solution
46               matrix X.
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48       LDB     (input) INTEGER
49               The leading dimension of the array B.  LDB >= 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
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57 LAPACK routine (version 3.1)    November 2006                       ZPPTRS(1)
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