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London Investment Mortgage Loan Information

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I have a rectangular data file, where one variable is a column of quoted character vectors. This variable will need to be further broken into a list of substrings, split by some delimiter. It is in the data file this way because for each observation (each subject/each row), they may have any amount of these substrings. In PHP, there is a function called explode that splits a string into an array of substrings, based on some delimiter. In R, strsplit accomplishes the same thing.

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A person on the R-Help list wanted to find the mean of each group, based on ID. Their data looked like:

data<-data.frame(ID=rep(letters[1:4], 5), size=runif(20))

The person was trying to write a for loop, as most people generally do when first encountering R (I sure did), but as is the case with most procedures in R, what can be done with a for loop in other languages, can be done looplessly in R.

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This is in the help files for rm, but for non-unix-ians, it seems to be hard to remember. Normally, if I am testing code that should stand on it's own, perhaps that I'll send off to the R-help list or put on here, I'll run this before I send it off:

rm(list=ls())

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This question was posed on R-Help; for the following data, "I would like to perform a simple matching but only row 1 compared to row 1, row 2 compared to row 2 (paired).......giving back a number as dissimilarity for each comparison."

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This question hit the R-help mailing list:

"I'm having trouble using the 'apply' function to multiply some arrays. Let A be a 500x2 array and B a 500x3 array. I need a vector C which has 6 columns being the first three the result of A[,1] * B and the second three the result of A[,2] * B. What is the most efficient way to express that? I'm trying to use 'apply' with no success..."

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