igroupProds {Rigroup}R Documentation

calculate products for small integer groups

Description

This function allows a user to quickly calculate the product for each small integer group of a data vector .

Usage

igroupProds(x,i,na.rm=TRUE)

Arguments

x A numeric, integer, or logical data vector
i A small integer vector indicating group membership 1:ngroups
na.rm if TRUE remove NAs before use (defaults to TRUE)

Details

This package provides a fast implementation for calculating products for each group in a data vector where a small integer vector (1:number of groups) indicates group membership. na.rm is used to determine how NAs are handled. The return value is a vector with length(number of groups).

Value

igroupProds: Returns a vector with length equal to the number of groups.

Author(s)

K. Hendricks with lots of help from B. Dunlap

References

None

See Also

igroupAlls igroupAnys igroupCounts igroupMaxs igroupMeans igroupMins igroupRanges igroupSums

Examples

x <- rnorm(100)
i <- rep(1:25,4)
prods <- igroupProds(x,i)
prods

[Package Rigroup version 0.83.0 Index]