File: cs_q1.m

package info (click to toggle)
suitesparse 1%3A5.8.1%2Bdfsg-2
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 152,716 kB
  • sloc: ansic: 774,385; cpp: 24,213; makefile: 6,310; fortran: 1,927; java: 1,826; csh: 1,686; ruby: 725; sh: 535; perl: 225; python: 209; sed: 164; awk: 60
file content (18 lines) | stat: -rw-r--r-- 387 bytes parent folder | download | duplicates (10) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
 
function Q = cs_q1 (V, Beta, p)
%CS_Q1 construct Q from Householder vectors
% Example:
%   Q = cs_q1 (V, beta, p)
% See also: testall

% Copyright 2006-2012, Timothy A. Davis, http://www.suitesparse.com

[m n] = size (V) ;
Q = speye (m) ;
if (nargin > 2)
    Q = Q (:,p) ;
end
for i = 1:m
    for k = 1:n
        Q (i,:) = Q (i,:) - ((Q(i,:) * V(:,k)) * Beta(k)) * V(:,k)' ;
    end
end