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March 2014 update

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Ingy döt Net 2014-04-02 16:56:35 +00:00
parent 09687c4926
commit a25938f123
1846 changed files with 21876 additions and 5203 deletions
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8
Task/Entropy/D/entropy.d
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@ -1,13 +1,13 @@
import std.stdio, std.algorithm, std.math;
double entropy(T)(T[] s)
/*pure nothrow*/ if (__traits(compiles, sort(s))) {
/*pure nothrow*/ if (__traits(compiles, s.sort())) {
return s
.sort()
.group
.map!(g => g[1] / cast(double)s.length)
.map!(p => -p * log2(p))
.reduce!q{a + b};
.map!(g => g[1] / double(s.length))
.map!(p => -p * p.log2)
.sum;
}
void main() {