Re: pattern matching
- To: mathgroup at smc.vnet.net
- Subject: [mg128317] Re: pattern matching
- From: Bill Rowe <readnews at sbcglobal.net>
- Date: Sat, 6 Oct 2012 01:52:12 -0400 (EDT)
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- Delivered-to: l-mathgroup@wolfram.com
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On 10/5/12 at 2:52 AM, dnlsnd777 at gmail.com (Daniel Sanders) wrote:
>Consider the following code:
>Count[Table[
>Count[Table[RandomInteger[], {n}], 1]/n, {n, 100, 1000, 10}], x_ <
>.5]
>I want to count the number of times there are occurrences less than
>.5 but some how I am not specifying the right pattern. Any
>suggestions on getting right?
You need to use PatternTest rather than just a pattern. That is:
In[13]:= MatchQ[.2, x_ < .5]
Out[13]= False
In[14]:= MatchQ[.2 , _?(# < .5 &)]
Out[14]= True