[R] Faster way to implement this search?

Walter Anderson wandrson01 at gmail.com
Fri Mar 16 17:59:37 CET 2012

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

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