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

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

11       SUBROUTINE DSPTRS( 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           DOUBLE         PRECISION AP( * ), B( LDB, * )
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PURPOSE

22       DSPTRS  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 DSPTRF.
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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       AP      (input) DOUBLE PRECISION array, dimension (N*(N+1)/2)
41               The block diagonal matrix D and the multipliers used to  obtain
42               the  factor  U  or  L as computed by DSPTRF, stored as a packed
43               triangular matrix.
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45       IPIV    (input) INTEGER array, dimension (N)
46               Details of the interchanges and the block  structure  of  D  as
47               determined by DSPTRF.
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49       B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)
50               On  entry, the right hand side matrix B.  On exit, the solution
51               matrix X.
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53       LDB     (input) INTEGER
54               The leading dimension of the array B.  LDB >= max(1,N).
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56       INFO    (output) INTEGER
57               = 0:  successful exit
58               < 0: if INFO = -i, the i-th argument had an illegal value
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62 LAPACK routine (version 3.2)    November 2008                       DSPTRS(1)
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