as.vmode: Coercing to virtual mode

In ff: Memory-Efficient Storage of Large Data on Disk and Fast Access Functions

Coercing to virtual mode

Description

as.vmode is a generic that converts some R ram object to the desired vmode.

Usage

as.vmode(x, ...)
as.boolean(x, ...)
as.quad(x, ...)
as.nibble(x, ...)
as.byte(x, ...)
as.ubyte(x, ...)
as.short(x, ...)
as.ushort(x, ...)
## Default S3 method:
as.vmode(x, vmode, ...)
## S3 method for class 'ff'
as.vmode(x, ...)
## Default S3 method:
as.boolean(x, ...)
## Default S3 method:
as.quad(x, ...)
## Default S3 method:
as.nibble(x, ...)
## Default S3 method:
as.byte(x, ...)
## Default S3 method:
as.ubyte(x, ...)
## Default S3 method:
as.short(x, ...)
## Default S3 method:
as.ushort(x, ...)

Arguments

x	any object
vmode	virtual mode
...	The ... don't have a function yet, they are only defined to keep the generic flexible.

Details

Function as.vmode actually coerces to one of the usual storage.modes (see .rammode) but flags them with an additional attribute 'vmode' if necessary. The coercion generics can also be called directly:

as.boolean	1 bit logical without NA
as.logical	2 bit logical with NA
as.quad	2 bit unsigned integer without NA
as.nibble	4 bit unsigned integer without NA
as.byte	8 bit signed integer with NA
as.ubyte	8 bit unsigned integer without NA
as.short	16 bit signed integer with NA
as.ushort	16 bit unsigned integer without NA
as.integer	32 bit signed integer with NA
as.single	32 bit float
as.double	64 bit float
as.complex	2x64 bit float
as.raw	8 bit unsigned char
as.character	character

Value

a vector of the desired vmode containing the input data

Author(s)

Jens Oehlschlägel

See Also

vmode, vector.vmode

Examples

  as.vmode(1:3,"double")
  as.vmode(1:3,"byte")
  as.double(1:3)
  as.byte(1:3)

ff documentation built on Feb. 16, 2023, 7:48 p.m.