alply {plyr} | R Documentation |
For each slice of an array, apply function then combine
results into a list. alply
is somewhat similar to
apply
for cases where the results are not
atomic.
alply(.data, .margins, .fun = NULL, ..., .expand = TRUE, .progress = "none", .parallel = FALSE)
.fun |
function to apply to each piece |
... |
other arguments passed on to |
.progress |
name of the progress bar to use, see
|
.data |
matrix, array or data frame to be processed |
.margins |
a vector giving the subscripts to split
up |
.expand |
if |
.parallel |
if |
list of results
This function splits matrices, arrays and data frames by dimensions
If there are no results, then this function will return a
list of length 0 (list()
).
Hadley Wickham (2011). The Split-Apply-Combine Strategy for Data Analysis. Journal of Statistical Software, 40(1), 1-29. http://www.jstatsoft.org/v40/i01/.
Other array input: aaply
,
adply
Other list output: dlply
,
llply
alply(ozone, 3, quantile) alply(ozone, 3, function(x) table(round(x)))