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Re: Integer Length Count
Posted:
Nov 24, 2012 2:41 AM


I think this meets your problem description:
Tally [ integerList // IntegerLength ]
Example:
f [ n_ ] := Module [ {maxInt, nInts, list }, maxInt = 1000000000; nInts = n; list = RandomInteger [ { 0, maxInt }, nInts ] ; Tally [ list // IntegerLength ] // Sort // AbsoluteTiming ] ; f[10]
The good news: f [ one hundred million ] runs in under 7 seconds (on my computer). The bad news: f [ one billion ] hangs (or runs inordinately long ).
HTH
On Fri, Nov 23, 2012 at 12:28 AM, <sylviehobbs@comcast.net> wrote: > > > I use a function in SAS that takes, in my case, a billion different integ= ers of varying length and counts the frequency of the length of each intege= r by converting the digits in the integers into alpha characters and counti= ng the frequency of the right most position of the alpha character. > > > > I am trying to do more and more routine programming in Mathematica and af= ter poking around in documentation for the past 4 hours have yet to find th= e parallel function in Mathematica for counting the integer frequency lengt= h in a big data set. My family wants me to drop everything and put the Turk= ey in the oven. My cat Sylvester even fell asleep on his back in front of t= he refrigerator with his little legs up in the air, so he want miss the tra= nsfer of the Turkey from the stove to the refrigerator. OH WELL  IT'S SHO= W TIME! > > > > Meanwhile, let me know any recommendations you have on a Mathematica func= tion that parallels the SAS Function. > > > > Sylvia Hobbs >



