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CentOS 7.0 - man page for sgttrs (centos section 3)

sgttrs.f(3)							      LAPACK							       sgttrs.f(3)

sgttrs.f -
Functions/Subroutines subroutine sgttrs (TRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB, INFO) SGTTRS Function/Subroutine Documentation subroutine sgttrs (characterTRANS, integerN, integerNRHS, real, dimension( * )DL, real, dimension( * )D, real, dimension( * )DU, real, dimension( * )DU2, integer, dimension( * )IPIV, real, dimension( ldb, * )B, integerLDB, integerINFO) SGTTRS Purpose: SGTTRS solves one of the systems of equations A*X = B or A**T*X = B, with a tridiagonal matrix A using the LU factorization computed by SGTTRF. Parameters: TRANS TRANS is CHARACTER*1 Specifies the form of the system of equations. = 'N': A * X = B (No transpose) = 'T': A**T* X = B (Transpose) = 'C': A**T* X = B (Conjugate transpose = Transpose) N N is INTEGER The order of the matrix A. NRHS NRHS is INTEGER The number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0. DL DL is REAL array, dimension (N-1) The (n-1) multipliers that define the matrix L from the LU factorization of A. D D is REAL array, dimension (N) The n diagonal elements of the upper triangular matrix U from the LU factorization of A. DU DU is REAL array, dimension (N-1) The (n-1) elements of the first super-diagonal of U. DU2 DU2 is REAL array, dimension (N-2) The (n-2) elements of the second super-diagonal of U. IPIV IPIV is INTEGER array, dimension (N) The pivot indices; for 1 <= i <= n, row i of the matrix was interchanged with row IPIV(i). IPIV(i) will always be either i or i+1; IPIV(i) = i indicates a row interchange was not required. B B is REAL array, dimension (LDB,NRHS) On entry, the matrix of right hand side vectors B. On exit, B is overwritten by the solution vectors X. LDB LDB is INTEGER The leading dimension of the array B. LDB >= max(1,N). INFO INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value Author: Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Date: September 2012 Definition at line 138 of file sgttrs.f. Author Generated automatically by Doxygen for LAPACK from the source code. Version 3.4.2 Tue Sep 25 2012 sgttrs.f(3)