Re: Counting Categories

• To: mathgroup at smc.vnet.net
• Subject: [mg96833] Re: [mg96798] Counting Categories
• From: DrMajorBob <btreat1 at austin.rr.com>
• Date: Thu, 26 Feb 2009 07:51:33 -0500 (EST)
• References: <200902250903.EAA15666@smc.vnet.net>

```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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