qrfac.m

来自「用matlab写的一些数值算法」· M 代码 · 共 13 行

function  [H, R] = qrfac(A)
% QR factorization of A by Householder transformations.
% Householder vectors are stored in H

% Version 11.12.2003.  INCBOX

[m,n] = size(A);  H = zeros(m,n);    % make room for vectors
for  k = 1 : n
  ii = k:m;   jj = k:n;            % active rows and columns
  H(ii,k) = househ(A(ii,k));            % Householder vector
  A(ii,jj) = apphouse(H(ii,k),A(ii,jj));         % transform 
end
R = triu(A(1:n,:));            % upper triangular n*n factor