Averages/Mode: Difference between revisions

===Versionversion 1===

<lang rexx>/*REXX program finds the mode (most occurring element) of a vector. */

/*════════vector══════════ ════════vector══════════─ ═══show vector═══ ════show result══════ ═─═══show result═════ */

v= 1 8 6 0 1 9 4 6 1 9 9 9 ; say 'vector='v; say 'mode='mode(v); say

v= 1 2 3 4 5 6 7 8 9 11 10 ; say 'vector='v; say 'mode='mode(v); say

v= 8 8 8 2 2 2 ; say 'vector='v; say 'mode='mode(v); say

v='cat kat Cat emu emu Kat' ; say 'vector='v; say 'mode='mode(v); say

exit /*stick a fork in it, we're all done. */

EsorteSort: procedure expose @.; parse arg # 1 h=@.0 /* [↓] this is an exchange sort. */

do while h>1; h=h%2 /*In REXX, % is /*% isan integer divide.*/

do i=1 for @.0#-h; j=i; k=h+i /* [↓] perform exchange for elements. */

do while @.k<@.j & h<j; _=@.j; @.j=@.k; @.k=_; j=j-h; k=k-h; end

end /*i*/

end /*while h>1*/

return

mode: procedure expose @.; parse arg x /*function finds the MODE of a vector. */

@.0 #=words(x) /*#: [↓]the makenumber anof arrayelements fromin vector.*/

do k=1 for @.0#; @.k=word(x,k); end /*k ◄──── make an array from the vector.*/

call EsorteSort # @.0 /*sort the elements in the array. */

?=@.1 /*assume 1stthe first element is the mode.*/

freq=1 /*the frequency of the occurrence. */

do j=1 for @.0#; _=j-freq /*traipse through the elements. in array*/

if @.j==@._ then do /*is this element the same as previous? */

freq=freq+1 /*bump the frequency counter. */

?=@.j /*this element is the mode, (···so far).*/

end

end /*j*/

return ? /*return the nodemode toof thevector to invoker.*/</lang>