from.dfs {rmr2}R Documentation

Read or write R objects from or to the file system

Description

Functions that read or write R objects from or to the file system

Usage

to.dfs(kv, output = dfs.tempfile(), format = "native")
from.dfs(input, format = "native")

Arguments

kv

A key-value pair; also, a vector, list, matrix or a data frame (in this case the keys will be set to NULL)

input

A valid path or a big.data.object

output

A valid path

format

For from.dfs either a string naming a format, the same as those allowed by make.input.format, or the value returned by make.input.format. The same is true for to.dfs, but refer to make.output.format instead.

Details

These functions allow to move data from RAM to the file system and back. Keep in mind that the capacity of these two storage media is different by two or more orders of magnitude, so the conversion will make sense only in specific situations. These functions do not perform any size control, so the responsibility is on the user. For the local backend, file system means the local file system. For the Hadooop backend it means HDFS

Value

from.dfs returns the object whose representation is contained in input. to.dfs returns the value of output or, when this is missing, a big.data.object

Examples

from.dfs(to.dfs(1:10))
from.dfs(to.dfs(keyval(1, 1:10)))

[Package rmr2 version 3.3.1 Index]