TESTING/LIN/zgtt01.f(3) Library Functions Manual TESTING/LIN/zgtt01.f(3) NAME TESTING/LIN/zgtt01.f SYNOPSIS Functions/Subroutines subroutine zgtt01 (n, dl, d, du, dlf, df, duf, du2, ipiv, work, ldwork, rwork, resid) ZGTT01 Function/Subroutine Documentation subroutine zgtt01 (integer n, complex*16, dimension( * ) dl, complex*16, dimension( * ) d, complex*16, dimension( * ) du, complex*16, dimension( * ) dlf, complex*16, dimension( * ) df, complex*16, dimension( * ) duf, complex*16, dimension( * ) du2, integer, dimension( * ) ipiv, complex*16, dimension( ldwork, * ) work, integer ldwork, double precision, dimension( * ) rwork, double precision resid) ZGTT01 Purpose: !> !> ZGTT01 reconstructs a tridiagonal matrix A from its LU factorization !> and computes the residual !> norm(L*U - A) / ( norm(A) * EPS ), !> where EPS is the machine epsilon. !> Parameters N !> N is INTEGER !> The order of the matrix A. N >= 0. !> DL !> DL is COMPLEX*16 array, dimension (N-1) !> The (n-1) sub-diagonal elements of A. !> D !> D is COMPLEX*16 array, dimension (N) !> The diagonal elements of A. !> DU !> DU is COMPLEX*16 array, dimension (N-1) !> The (n-1) super-diagonal elements of A. !> DLF !> DLF is COMPLEX*16 array, dimension (N-1) !> The (n-1) multipliers that define the matrix L from the !> LU factorization of A. !> DF !> DF is COMPLEX*16 array, dimension (N) !> The n diagonal elements of the upper triangular matrix U from !> the LU factorization of A. !> DUF !> DUF is COMPLEX*16 array, dimension (N-1) !> The (n-1) elements of the first super-diagonal of U. !> DU2 !> DU2 is COMPLEX*16 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. !> WORK !> WORK is COMPLEX*16 array, dimension (LDWORK,N) !> LDWORK !> LDWORK is INTEGER !> The leading dimension of the array WORK. LDWORK >= max(1,N). !> RWORK !> RWORK is DOUBLE PRECISION array, dimension (N) !> RESID !> RESID is DOUBLE PRECISION !> The scaled residual: norm(L*U - A) / (norm(A) * EPS) !> Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Definition at line 132 of file zgtt01.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 TESTING/LIN/zgtt01.f(3)