10 lines
311 B
Tcl
10 lines
311 B
Tcl
proc entropy {str} {
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set log2 [expr log(2)]
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foreach char [split $str ""] {dict incr counts $char}
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set entropy 0.0
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foreach count [dict values $counts] {
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set freq [expr {$count / double([string length $str])}]
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set entropy [expr {$entropy - $freq * log($freq)/$log2}]
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}
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return $entropy
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}
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