ffbase (version 0.6-2)

transform.ffdf: Transform a ffdf data.frame

Description

Same functionality as transform, but on a ffdf object. Please note that you should write your expression as if it is a normal data.frame. The resulting data.frame however will be a ffdf data.frame.

Usage

## S3 method for class 'ffdf':
transform(`_data`, \dots)

Arguments

_data

ffdf data object to be transformed.

...

named arguments that will be added to the ffdf data.frame

Value

• a modified clone of `_data`.

Examples

transform(as.ffdf(airquality), Ozone = -Ozone)
transform(as.ffdf(airquality), new = -Ozone, Temp = (Temp-32)/1.8)