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

6       SSYTRS  -  solves a system of linear equations A*X = B with a real sym‐
7       metric matrix A using the factorization A = U*D*U**T or  A  =  L*D*L**T
8       computed by SSYTRF
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SYNOPSIS

11       SUBROUTINE SSYTRS( UPLO, N, NRHS, A, LDA, IPIV, B, LDB, INFO )
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13           CHARACTER      UPLO
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15           INTEGER        INFO, LDA, LDB, N, NRHS
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17           INTEGER        IPIV( * )
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19           REAL           A( LDA, * ), B( LDB, * )
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PURPOSE

22       SSYTRS  solves a system of linear equations A*X = B with a real symmet‐
23       ric matrix A using the factorization A = U*D*U**T or A = L*D*L**T  com‐
24       puted by SSYTRF.
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ARGUMENTS

27       UPLO    (input) CHARACTER*1
28               Specifies  whether  the details of the factorization are stored
29               as an upper or lower triangular matrix.  = 'U':  Upper triangu‐
30               lar, form is A = U*D*U**T;
31               = 'L':  Lower triangular, form is A = L*D*L**T.
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33       N       (input) INTEGER
34               The order of the matrix A.  N >= 0.
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36       NRHS    (input) INTEGER
37               The  number of right hand sides, i.e., the number of columns of
38               the matrix B.  NRHS >= 0.
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40       A       (input) REAL array, dimension (LDA,N)
41               The block diagonal matrix D and the multipliers used to  obtain
42               the factor U or L as computed by SSYTRF.
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44       LDA     (input) INTEGER
45               The leading dimension of the array A.  LDA >= max(1,N).
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47       IPIV    (input) INTEGER array, dimension (N)
48               Details  of  the  interchanges  and the block structure of D as
49               determined by SSYTRF.
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51       B       (input/output) REAL array, dimension (LDB,NRHS)
52               On entry, the right hand side matrix B.  On exit, the  solution
53               matrix X.
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55       LDB     (input) INTEGER
56               The leading dimension of the array B.  LDB >= max(1,N).
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58       INFO    (output) INTEGER
59               = 0:  successful exit
60               < 0:  if INFO = -i, the i-th argument had an illegal value
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64 LAPACK routine (version 3.2)    November 2008                       SSYTRS(1)
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