TESTING/LIN/cgtt02.f(3) Library Functions Manual TESTING/LIN/cgtt02.f(3) NAME TESTING/LIN/cgtt02.f SYNOPSIS Functions/Subroutines subroutine cgtt02 (trans, n, nrhs, dl, d, du, x, ldx, b, ldb, resid) CGTT02 Function/Subroutine Documentation subroutine cgtt02 (character trans, integer n, integer nrhs, complex, dimension( * ) dl, complex, dimension( * ) d, complex, dimension( * ) du, complex, dimension( ldx, * ) x, integer ldx, complex, dimension( ldb, * ) b, integer ldb, real resid) CGTT02 Purpose: CGTT02 computes the residual for the solution to a tridiagonal system of equations: RESID = norm(B - op(A)*X) / (norm(op(A)) * norm(X) * EPS), where EPS is the machine epsilon. Parameters TRANS TRANS is CHARACTER Specifies the form of the residual. = 'N': B - A * X (No transpose) = 'T': B - A**T * X (Transpose) = 'C': B - A**H * X (Conjugate transpose) N N is INTEGER The order of the matrix A. N >= 0. NRHS NRHS is INTEGER The number of right hand sides, i.e., the number of columns of the matrices B and X. NRHS >= 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. X X is COMPLEX array, dimension (LDX,NRHS) The computed solution vectors X. LDX LDX is INTEGER The leading dimension of the array X. LDX >= max(1,N). B B is COMPLEX array, dimension (LDB,NRHS) On entry, the right hand side vectors for the system of linear equations. On exit, B is overwritten with the difference B - op(A)*X. LDB LDB is INTEGER The leading dimension of the array B. LDB >= max(1,N). RESID RESID is REAL norm(B - op(A)*X) / (norm(op(A)) * norm(X) * EPS) Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Definition at line 122 of file cgtt02.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 TESTING/LIN/cgtt02.f(3)