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Re: Counting Categories

  • To: mathgroup at smc.vnet.net
  • Subject: [mg96853] Re: [mg96798] Counting Categories
  • From: Gregory Lypny <gregory.lypny at videotron.ca>
  • Date: Thu, 26 Feb 2009 07:55:12 -0500 (EST)
  • References: <200902250903.EAA15666@smc.vnet.net>

This is so cool.  Thank you.  I also found a new function yesterday  
called GatherBy.  Not sure if it does the same thing.

Regards,

	Gregory


On Wed, Feb 25, 2009, at 5:21 AM, DrMajorBob wrote:

> Something like:
>
> colors = {red, yellow, green, blue};
> sizes = {small, medium, large};
> randomColor := RandomChoice@colors
> randomSize := RandomChoice@sizes
> pairs = Table[{randomColor, randomSize}, {50}];
>
> Partition[Count[pairs, #] & /@ Tuples[{colors, sizes}], Length@sizes]
>
> {{5, 3, 3}, {3, 6, 3}, {8, 1, 2}, {5, 4, 7}}
>
> or
>
> Apply[Count[pairs, {##}, 1] &, Outer[List, colors, sizes], {2}]
>
> {{5, 3, 3}, {3, 6, 3}, {8, 1, 2}, {5, 4, 7}}
>
> Bobby
>
> On Wed, 25 Feb 2009 03:03:33 -0600, Gregory Lypny <gregory.lypny at videotron.ca 
> > wrote:
>
>> Hello Everyone,
>>
>> I'm trying to do multivariate category counts in the way that used to
>> be handled by CategoryCounts but is now replaced by Cases.  The
>> example in Help simply applies Cases twice to find the count of
>> elements in a list that are numbers and the count that is even.
>>
>> Map[Cases[{a, b, c, 1, 2, d, 3}, #] &, {_?NumberQ, _?EvenQ}]
>>
>> {{1, 2, 3}, {2}}
>>
>> But what if I have many rows of observations on two dimensions
>> (columns) such as red, blue, green, and small, medium, big?  I'd like
>> to be able categorize them accordingly as the count of small and red,
>> medium and red, big and red, and so on.  Any way to do that?
>>
>> 	Regards,
>>
>> 		Gregory
>>
>>
>>
>>
>
>
>
> -- 
> DrMajorBob at longhorns.com



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