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

6       SSYTRS  -  a  system  of linear equations A*X = B with a real symmetric
7       matrix A using the factorization A = U*D*U**T or A = L*D*L**T  computed
8       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

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       A       (input) REAL array, dimension (LDA,N)
42               The block diagonal matrix D and the multipliers used to  obtain
43               the factor U or L as computed by SSYTRF.
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45       LDA     (input) INTEGER
46               The leading dimension of the array A.  LDA >= max(1,N).
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48       IPIV    (input) INTEGER array, dimension (N)
49               Details  of  the  interchanges  and the block structure of D as
50               determined by SSYTRF.
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52       B       (input/output) REAL array, dimension (LDB,NRHS)
53               On entry, the right hand side matrix B.  On exit, the  solution
54               matrix X.
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56       LDB     (input) INTEGER
57               The leading dimension of the array B.  LDB >= max(1,N).
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59       INFO    (output) INTEGER
60               = 0:  successful exit
61               < 0:  if INFO = -i, the i-th argument had an illegal value
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65 LAPACK routine (version 3.1)    November 2006                       SSYTRS(1)
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