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NAME SPOTRS - solve a system of linear equations A*X = B with a symmetric positive definite matrix A using the Cholesky fac- torization A = U**T*U or A = L*L**T computed by SPOTRF SYNOPSIS SUBROUTINE SPOTRS( UPLO, N, NRHS, A, LDA, B, LDB, INFO ) CHARACTER UPLO INTEGER INFO, LDA, LDB, N, NRHS REAL A( LDA, * ), B( LDB, * ) PURPOSE SPOTRS solves a system of linear equations A*X = B with a symmetric positive definite matrix A using the Cholesky fac- torization A = U**T*U or A = L*L**T computed by SPOTRF. ARGUMENTS UPLO (input) CHARACTER*1 = 'U': Upper triangle of A is stored; = 'L': Lower triangle of A is stored. N (input) INTEGER The order of the matrix A. N >= 0. NRHS (input) INTEGER The number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0. A (input) REAL array, dimension (LDA,N) The triangular factor U or L from the Cholesky fac- torization A = U**T*U or A = L*L**T, as computed by SPOTRF. LDA (input) INTEGER The leading dimension of the array A. LDA >= max(1,N). B (input/output) REAL array, dimension (LDB,NRHS) On entry, the right hand side matrix B. On exit, the solution matrix X. LDB (input) INTEGER The leading dimension of the array B. LDB >= max(1,N). INFO (output) INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value