plyr (version 1.8.9)

idata.frame: Construct an immutable data frame.

Description

An immutable data frame works like an ordinary data frame, except that when you subset it, it returns a reference to the original data frame, not a a copy. This makes subsetting substantially faster and has a big impact when you are working with large datasets with many groups.

Usage

idata.frame(df)

Value

an immutable data frame

Arguments

df

a data frame

Details

This method is still a little experimental, so please let me know if you run into any problems.

Examples

Run this code
system.time(dlply(baseball, "id", nrow))
system.time(dlply(idata.frame(baseball), "id", nrow))

Run the code above in your browser using DataLab