Entropy: Difference between revisions

=={{header|Arturo}}==

<lang rebol>entropy: function [s][

t: #[]

loop s 'c [

unless key? t c -> t\[c]: 0

t\[c]: t\[c] + 1

]

result: new 0

loop values t 'x ->

'result - (x//(size s)) * log x//(size s) 2

return result

]

print entropy "1223334444"</lang>

{{out}}

<pre>1.846439344671015</pre>