[R] Faster way to implement this search?

Walter Anderson wandrson01 at gmail.com
Fri Mar 16 23:47:22 CET 2012

On 03/16/2012 12:23 PM, Sarah Goslee wrote:
> There's almost certainly a better way, but I'd be more inclined to look for
> it if you'd provide a small reproducible example so I could actually try it.
> Without knowing the structure of your data, it's very hard to offer
> alternatives.
> Sarah
> On Fri, Mar 16, 2012 at 12:59 PM, Walter Anderson<wandrson01 at gmail.com>  wrote:
>> I am working on a simulation where I need to count the number of matches for
>> an arbitrary pattern in a large sequence of binomial factors.  My current
>> code is
>>     for(indx in 1:(length(bin.05)-3))
>>       if ((bin.05[indx] == test.pattern[1])&&  (bin.05[indx+1] ==
>> test.pattern[2])&&  (bin.05[indx+2] == test.pattern[3]))
>>         return.values$count.match.pattern[1] =
>> return.values$count.match.pattern[1] + 1
>> Since I am running the above code for each simulation multiple times on
>> sequences of 10,000,000 factors the code is taking longer than I would like.
>>    Is there a better (more "R" way of achieving the same answer?
>> Walter Anderson
Thank you for responding.  I was attempting to keep my code snippet 
small, since my last question which contained what I thought was a small 
(but complete example) only received responses that the
provided code was not succinct enough.

the provided sequence of factors (bin.05) consist of a vector of up of 
factors like this; [T,T,O,T,O,O,T,T,T,...] in a variety of different 
proportions.  The search pattern consists of any one of the combinations 
of the factors (T & O) in a set of three, ie. [T,T,O]

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