ffbase (version 0.13.3)

condSum: Fast conditional sum

Description

condSum works like a very fast version of tapply with FUN=sum.

Usage

condSum(x, index, na.rm = FALSE, ...)

Arguments

x

numeric vector to be summed

index

(list of) factor(s) for which the sum will be calculated

na.rm

logical If TRUE NA values will be removed

...

not used

Value

array with dimensions of index