TESTING/LIN/cgtt01.f(3) Library Functions Manual TESTING/LIN/cgtt01.f(3) NAME TESTING/LIN/cgtt01.f SYNOPSIS Functions/Subroutines subroutine cgtt01 (n, dl, d, du, dlf, df, duf, du2, ipiv, work, ldwork, rwork, resid) CGTT01 Function/Subroutine Documentation subroutine cgtt01 (integer n, complex, dimension( * ) dl, complex, dimension( * ) d, complex, dimension( * ) du, complex, dimension( * ) dlf, complex, dimension( * ) df, complex, dimension( * ) duf, complex, dimension( * ) du2, integer, dimension( * ) ipiv, complex, dimension( ldwork, * ) work, integer ldwork, real, dimension( * ) rwork, real resid) CGTT01 Purpose: CGTT01 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 array, dimension (N-1) The (n-1) sub-diagonal elements of A. D D is COMPLEX array, dimension (N) The diagonal elements of A. DU DU is COMPLEX array, dimension (N-1) The (n-1) super-diagonal elements of A. DLF DLF is COMPLEX array, dimension (N-1) The (n-1) multipliers that define the matrix L from the LU factorization of A. DF DF is COMPLEX array, dimension (N) The n diagonal elements of the upper triangular matrix U from the LU factorization of A. DUF DUF is COMPLEX array, dimension (N-1) The (n-1) elements of the first super-diagonal of U. DU2 DU2 is COMPLEX 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 array, dimension (LDWORK,N) LDWORK LDWORK is INTEGER The leading dimension of the array WORK. LDWORK >= max(1,N). RWORK RWORK is REAL array, dimension (N) RESID RESID is REAL 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 cgtt01.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 TESTING/LIN/cgtt01.f(3)