gusucode.com > 《MATLAB图像与视频处理实用案例详解》代码 > 《MATLAB图像与视频处理实用案例详解》代码/第 19 章 基于语音识别的信号灯图像模拟控制技术/voicebox/disteusq.m
function d=disteusq(x,y,mode,w) %DISTEUSQ calculate euclidean, squared euclidean or mahanalobis distance D=(X,Y,MODE,W) % % Inputs: X,Y Vector sets to be compared. Each row contains a data vector. % X and Y must have the same number of columns. % % MODE Character string selecting the following options: % 'x' Calculate the full distance matrix from every row of X to every row of Y % 'd' Calculate only the distance between corresponding rows of X and Y % The default is 'd' if X and Y have the same number of rows otherwise 'x'. % 's' take the square-root of the result to give the euclidean distance. % % W Optional weighting matrix: the distance calculated is (x-y)*W*(x-y)' % If W is a vector, then the matrix diag(W) is used. % % Output: D If MODE='d' then D is a column vector with the same number of rows as the shorter of X and Y. % If MODE='x' then D is a matrix with the same number of rows as X and the same number of columns as Y'. % % Copyright (C) Mike Brookes 1998 % Version: $Id: disteusq.m,v 1.6 2010/04/19 16:56:22 dmb Exp $ % % VOICEBOX is a MATLAB toolbox for speech processing. % Home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % This program is free software; you can redistribute it and/or modify % it under the terms of the GNU General Public License as published by % the Free Software Foundation; either version 2 of the License, or % (at your option) any later version. % % This program is distributed in the hope that it will be useful, % but WITHOUT ANY WARRANTY; without even the implied warranty of % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the % GNU General Public License for more details. % % You can obtain a copy of the GNU General Public License from % http://www.gnu.org/copyleft/gpl.html or by writing to % Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% [nx,p]=size(x); ny=size(y,1); if nargin<3 | isempty(mode) mode='0'; end if any(mode=='d') | (mode~='x' & nx==ny) % Do pairwise distance calculation nx=min(nx,ny); z=double(x(1:nx,:))-double(y(1:nx,:)); if nargin<4 d=sum(z.*conj(z),2); elseif min(size(w))==1 wv=w(:).'; d=sum(z.*wv(ones(size(z,1),1),:).*conj(z),2); else d=sum(z*w.*conj(z),2); end else % Calculate full distance matrix if p>1 % x and y are matrices if nargin<4 z=permute(double(x(:,:,ones(1,ny))),[1 3 2])-permute(double(y(:,:,ones(1,nx))),[3 1 2]); d=sum(z.*conj(z),3); else nxy=nx*ny; z=reshape(permute(double(x(:,:,ones(1,ny))),[1 3 2])-permute(double(y(:,:,ones(1,nx))),[3 1 2]),nxy,p); if min(size(w))==1 wv=w(:).'; d=reshape(sum(z.*wv(ones(nxy,1),:).*conj(z),2),nx,ny); else d=reshape(sum(z*w.*conj(z),2),nx,ny); end end else % x and y are vectors z=double(x(:,ones(1,ny)))-double(y(:,ones(1,nx))).'; if nargin<4 d=z.*conj(z); else d=w*z.*conj(z); end end end if any(mode=='s') d=sqrt(d); end