[R] removing for-loop question

[Jeff D. Hamann]

R-loop-killers:

I'm looking for a hint to remove the loops from this little piece of code.

Since most of the of computing I deal with is very "loop-centric", it's
often difficult for me to translate index-based code into loop-free code.
Does anyone have any hints for speeding this up?

The actuals is a data.frame object and the resids is a simple matrix...

  cb <- cov( rbind( actuals$tvolh, resids[,5] ) )
  covb <- 0
  for( i in 1:nrow( actuals ) ) {
    for( j in 2:nrow( actuals ) ) {
      covb <- covb + actuals[i,]$ha * block.acts[j,]$ha * cb[i,j]
    }
  }


thanks,
Jeff.


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