1SPOTRS(1) LAPACK routine (version 3.2) SPOTRS(1)
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6 SPOTRS - solves a system of linear equations A*X = B with a symmetric
7 positive definite matrix A using the Cholesky factorization A = U**T*U
8 or A = L*L**T computed by SPOTRF
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11 SUBROUTINE SPOTRS( UPLO, N, NRHS, A, LDA, 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 REAL A( LDA, * ), B( LDB, * )
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20 SPOTRS solves a system of linear equations A*X = B with a symmetric
21 positive definite matrix A using the Cholesky factorization A = U**T*U
22 or A = L*L**T computed by SPOTRF.
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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 A (input) REAL array, dimension (LDA,N)
37 The triangular factor U or L from the Cholesky factorization A
38 = U**T*U or A = L*L**T, as computed by SPOTRF.
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40 LDA (input) INTEGER
41 The leading dimension of the array A. LDA >= max(1,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 SPOTRS(1)