R: Transform a ffdf data.frame

transform.ffdf {ffbase} | R Documentation

## 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`, ...)

### 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)

[Package ffbase version 0.13.1 Index]