srckeep {disk.frame}R Documentation

Keep only the variables from the input listed in selections

Description

Keep only the variables from the input listed in selections

Usage

srckeep(diskf, selections, ...)

srckeepchunks(diskf, chunks, ...)

Arguments

diskf

a disk.frame

selections

The list of variables to keep from the input source

...

not yet used

chunks

The chunks to load

Examples

cars.df = as.disk.frame(cars)

# when loading cars's chunks into RAM, load only the column speed
collect(srckeep(cars.df, "speed"))

# clean up cars.df
delete(cars.df)

[Package disk.frame version 0.3.7 Index]