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rsplitdataframeplyr

Split data frame into rows of fixed size

I have a bunch of data frames with varying degrees of length, ranging from approx. 15,000 to 500,000. For each of these data frames, I would like to split them up into smaller data frames each with 300 rows which I would do further processing on. How can I do this?

This (Split up a dataframe by number of rows) provides a partial answer, but it doesn't work because not all my data frames have length that are multiples of 300.

I would greatly appreciate it if a plyr and non-plyr solution can both be provided.

Solution

  • I don't understand why a plyr solution is needed. split works perfectly well and even hadley himself didn't suggest a plyr/reshape2 solution when he looked at the earlier question:

    split(dfrm, (0:nrow(dfrm) %/% 300)  # modulo division

    Does produce a warning but since you were expecting a non-evenly divisible result you should ignore it.