7 lines
162 B
Matlab
7 lines
162 B
Matlab
function E = entropy(d)
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if ischar(d), d=abs(d); end;
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[Y,I,J] = unique(d);
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H = sparse(J,1,1);
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p = full(H(H>0))/length(d);
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E = -sum(p.*log2(p));
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end;
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