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

6       SPPTRS  -  solves a system of linear equations A*X = B with a symmetric
7       positive definite matrix A in packed storage using the Cholesky factor‐
8       ization A = U**T*U or A = L*L**T computed by SPPTRF
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SYNOPSIS

11       SUBROUTINE SPPTRS( 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           REAL           AP( * ), B( LDB, * )
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PURPOSE

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

25       UPLO    (input) CHARACTER*1
26               = 'U':  Upper triangle of A is stored;
27               = 'L':  Lower triangle of A is stored.
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29       N       (input) INTEGER
30               The order of the matrix A.  N >= 0.
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32       NRHS    (input) INTEGER
33               The  number of right hand sides, i.e., the number of columns of
34               the matrix B.  NRHS >= 0.
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36       AP      (input) REAL array, dimension (N*(N+1)/2)
37               The triangular factor U or L from the Cholesky factorization  A
38               =  U**T*U  or  A = L*L**T, packed columnwise in a linear array.
39               The j-th column of U or L is stored in the array AP as follows:
40               if  UPLO = 'U', AP(i + (j-1)*j/2) = U(i,j) for 1<=i<=j; if UPLO
41               = 'L', AP(i + (j-1)*(2n-j)/2) = L(i,j) for j<=i<=n.
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43       B       (input/output) REAL array, dimension (LDB,NRHS)
44               On entry, the right hand side matrix B.  On exit, the  solution
45               matrix X.
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47       LDB     (input) INTEGER
48               The leading dimension of the array B.  LDB >= max(1,N).
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50       INFO    (output) INTEGER
51               = 0:  successful exit
52               < 0:  if INFO = -i, the i-th argument had an illegal value
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56 LAPACK routine (version 3.2)    November 2008                       SPPTRS(1)
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