gusucode.com > 支持向量机工具箱 - LIBSVM OSU_SVM LS_SVM源码程序 > 支持向量机工具箱 - LIBSVM OSU_SVM LS_SVM\stprtool\quadrat\qtransf.m
function [Y]=qtransf(X) % QTRANSF non-linear data mapping for quadratic function. % [Y]=qtransf(X) % % QTRANSF performs explicite non-linear data mapping for % quadratic discriminant function. A quadratic separation % surface in an original feature space X is mapped to a % separation hyperplane in a new feature space Y. % % Input: % X [NxK] contains K points in the original n-dimensional input space. % % Output: % Y [MxK] contains images of X in the new feature space. % % where N is dimension of the input space, % M = 2*N+N*(N-1)/2 is dimension of the new feature space, % K is number of mapped points. % % See also QUADEMO, L2Q2D, PQUAD2D. % % Statistical Pattern Recognition Toolbox, Vojtech Franc, Vaclav Hlavac % (c) Czech Technical University Prague, http://cmp.felk.cvut.cz % Written Vojtech Franc (diploma thesis) 19.11.1999, 23.12.1999 % Modifications % 26-June-2001, V.Franc, comments repared. % 24. 6.00 V. Hlavac, comments polished. % dimension N=size(X,1); % # of points K=size(X,2); % dimension of the new space N2=2*N+N*(N-1)/2; y=zeros(N2,K); % first N members Y(1:N,:)=X; member=N+1; for i=1:N, for j=i:N, Y(member,:)=X(i,:).*X(j,:); member=member+1; end end