1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
|
function x = cs_utsolve (U,b) %#ok
%CS_UTSOLVE solve a sparse lower triangular system U'*x=b.
% x = cs_utsolve(U,b) computes x = U'\b, U must be upper triangular with a
% zero-free diagonal. b must be a full vector.
%
% Example:
% Prob = ssget ('HB/arc130') ; A = Prob.A ; n = size (A,1) ;
% b = rand (n,1);
% [L U p q] = cs_lu (A) ;
% x = cs_ltsolve (L, cs_utsolve (U, b(q))) ; % x = L' \ (U' \ b(q)) ;
% x (p) = x ;
% norm (A'*x-b)
%
% See also CS_LSOLVE, CS_LTSOLVE, CS_USOLVE, MLDIVIDE.
% CXSparse, Copyright (c) 2006-2022, Timothy A. Davis. All Rights Reserved.
% SPDX-License-Identifier: LGPL-2.1+
error ('cs_utsolve mexFunction not found') ;
|
