RosettaCodeData/Task/Entropy/OoRexx/entropy.rexx
2023-07-01 13:44:08 -04:00

32 lines
456 B
Rexx

/* REXX */
Numeric Digits 16
Parse Arg s
If s='' Then
s="1223334444"
occ.=0
chars=''
n=0
cn=0
Do i=1 To length(s)
c=substr(s,i,1)
If pos(c,chars)=0 Then Do
cn=cn+1
chars=chars||c
End
occ.c=occ.c+1
n=n+1
End
do ci=1 To cn
c=substr(chars,ci,1)
p.c=occ.c/n
/* say c p.c */
End
e=0
Do ci=1 To cn
c=substr(chars,ci,1)
e=e+p.c*rxcalclog(p.c)/rxcalclog(2)
End
Say s 'Entropy' format(-e,,12)
Exit
::requires 'rxmath' LIBRARY