File size: 1,903 Bytes
d4035c1 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 |
function [K K_test]= kernel(X, Y, kernelName, wantK)
% KL2 sum X .* Y
% KL1 sum min (X, Y)
% KCHI2 2 * sum (X .* Y) ./ (X + Y)
% KHELL (X .* Y) .^ 0.5
if (wantK || strcmp(kernelName,'echi2')==1 || strcmp(kernelName,'emd')==1 || strcmp(kernelName,'rbf')==1)
switch kernelName
case 'emd'
K = emd_dist(X,X);
mu= 1 ./ mean(K(:)) ;
K = exp(- mu * K) ;
case 'echi2'
K = alldist2(X, 'chi2') ;
mu= 1 ./ mean(K(:)) ;
K = exp(- mu * K) ;
case 'kl1' %hist_intersect
K = vl_alldist2(X, 'kl1');
case'kl2'
K = X' * X ;
case 'kchi2'
K = vl_alldist2(X, 'kchi2') ;
case 'gb'
K = gbDistance(X, X);
case 'rbf'
X = X';
norm1 = sum(X.^2,2);
norm2 = sum(X.^2,2);
dist = (repmat(norm1 ,1,size(X,1)) + repmat(norm2',size(X,1),1) - 2*X*X');
mu=sqrt(mean(dist(:))/2);
K = exp(-0.5/mu^2 * dist);
end
if ~isempty(find(isnan(K)))
disp('something element is NaN in the K matrix');
K(find(isnan(K)))=10^20;
end
else
K = [];
end
switch kernelName
case 'emd'
K_test = emd_dist(X, Y);
K_test = exp(- mu * K_test) ;
case 'echi2'
K_test = vl_alldist(X, Y, 'chi2') ;
K_test = exp(- mu * K_test) ;
case 'kl1' %hist_intersect
K_test = vl_alldist2(X, Y, 'kl1');
case'kl2'
K_test = X' * Y ;
case 'kchi2'
K_test = vl_alldist2(X, Y, 'kchi2') ;
case 'gb'
K_test = gbDistance(X, Y);
case 'rbf'
Y = Y';
norm1 = sum(X.^2,2);
norm2 = sum(Y.^2,2);
dist = (repmat(norm1 ,1,size(Y,1)) + repmat(norm2',size(X,1),1) - 2*X*Y');
%mu=sqrt(mean(dist(:))/2);
K_test = exp(-0.5/mu^2 * dist);
end
if ~isempty(find(isnan(K_test)))
disp('something element is NaN in the K_test matrix');
K_test(find(isnan(K_test)))=10^20;
end |