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

6       SSPTRS  -  a  system  of linear equations A*X = B with a real symmetric
7       matrix A stored in packed format using the factorization A  =  U*D*U**T
8       or A = L*D*L**T computed by SSPTRF
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SYNOPSIS

11       SUBROUTINE SSPTRS( UPLO, N, NRHS, AP, IPIV, 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           INTEGER        IPIV( * )
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19           REAL           AP( * ), B( LDB, * )
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PURPOSE

22       SSPTRS  solves a system of linear equations A*X = B with a real symmet‐
23       ric matrix A stored in  packed  format  using  the  factorization  A  =
24       U*D*U**T or A = L*D*L**T computed by SSPTRF.
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ARGUMENTS

28       UPLO    (input) CHARACTER*1
29               Specifies  whether  the details of the factorization are stored
30               as an upper or lower triangular matrix.  = 'U':  Upper triangu‐
31               lar, form is A = U*D*U**T;
32               = 'L':  Lower triangular, form is A = L*D*L**T.
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34       N       (input) INTEGER
35               The order of the matrix A.  N >= 0.
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37       NRHS    (input) INTEGER
38               The  number of right hand sides, i.e., the number of columns of
39               the matrix B.  NRHS >= 0.
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41       AP      (input) REAL array, dimension (N*(N+1)/2)
42               The block diagonal matrix D and the multipliers used to  obtain
43               the  factor  U  or  L as computed by SSPTRF, stored as a packed
44               triangular matrix.
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46       IPIV    (input) INTEGER array, dimension (N)
47               Details of the interchanges and the block  structure  of  D  as
48               determined by SSPTRF.
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50       B       (input/output) REAL array, dimension (LDB,NRHS)
51               On  entry, the right hand side matrix B.  On exit, the solution
52               matrix X.
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54       LDB     (input) INTEGER
55               The leading dimension of the array B.  LDB >= max(1,N).
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57       INFO    (output) INTEGER
58               = 0:  successful exit
59               < 0: if INFO = -i, the i-th argument had an illegal value
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63 LAPACK routine (version 3.1)    November 2006                       SSPTRS(1)
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