is.open: Test if object is opened

In kindlychung/ff: memory-efficient storage of large data on disk and fast access functions

Description

Test whether an ff or ffdf object or a ff_pointer is opened.

Usage

is.open(x, ...)
## S3 method for class 'ff'
is.open(x, ...)
## S3 method for class 'ffdf'
is.open(x, ...)
## S3 method for class 'ff_pointer'
is.open(x, ...)

Arguments

x	an ff or ffdf object
...	further arguments (not used)

Details

ff objects open automatically if accessed while closed. For ffdf objects we test all of their physical components including their row.names if they are is.ff

Value

TRUE or FALSE (or NA if not all components of an ffdf object are opened or closed)

Author(s)

Jens Oehlschl<c3><a4>gel

See Also

is.readonly, open.ff, close.ff

Examples

  x <- ff(1:12)
  is.open(x)
  close(x)
  is.open(x)
  rm(x); gc()

kindlychung/ff documentation built on May 20, 2019, 9:58 a.m.