utilities: Printing, reading and writing compiled function objects
In eddelbuettel/inline: Functions to Inline C, C++, Fortran Function Calls from R

utilities

R Documentation

Printing, reading and writing compiled function objects

Description

moveDLL moves the DLL used by a compiled function to a user defined location.

writeCFunc saves a CFunc object after the DLL has been moved to the desired location using moveDLL.

readCFunc reads a CFunc object that has been saved using writeCFunc.

The print and code methods respectively print the entire object or only the code parts.

Usage

moveDLL(x, ...)
## S4 method for signature 'CFunc'
moveDLL(x, name, directory, unload = FALSE, overwrite = FALSE, verbose = FALSE)

writeCFunc(x, file)
readCFunc(file)

## S4 method for signature 'CFunc'
print(x)
## S4 method for signature 'CFuncList'
print(x)

## S4 method for signature 'CFunc'
code(x, linenumbers = TRUE)
## S4 method for signature 'CFuncList'
code(x, linenumbers = TRUE)

Arguments

`x`	A `CFunc` or `CFuncList` object as created by `cfunction`
`name`	The base of the file name that the DLL should be moved to. The file name extension will depend on the operating system used
`directory`	The directory that the DLL should be written to
`unload`	In case the new path constructed from `name` and `directory` points to a loaded DLL, should we unload it?
`overwrite`	In case there is a file at the new path constructed from `name` and `directory` should we overwrite that file?
`verbose`	Should we print a message stating where the DLL was copied if the operation was successful?
`file`	The file path for writing and reading the object generated by `cfunction`. Consider using a file name extension like `.rda` or `.RData` to indicate that this is a serialized R object.
`linenumbers`	If `TRUE` all code lines will be numbered.
`...`	May be used in future methods

Details

If you move the DLL to a user defined location with moveDLL, this will keep an on-disk copy of the DLL which will prevent it from being lost at session termination - unless written to the session tempdir. Saving and reloading the CFunc object with standard tools like save or saveRDS will still loose the pointer to the DLL. However, when the DLL has been moved using moveDLL, CFunc objects can be saved by writeCFunc and restored by readCFunc.

Value

Function readDynLib returns a CFunc object.

Function writeDynLib returns the name of the .CFunc file that was created.

Note

The code of a CFunc or CFuncList object x can be extracted (rather than printed), using:

x@code.
To write the code to a file (here called "fn"), without the new-line character "\n":

write (strsplit(x, "\n")[[1]], file = "fn")

Author(s)

Karline Soetaert and Johannes Ranke

Examples


x <- as.numeric(1:10)
n <- as.integer(10)

code <- "
      integer i
      do 1 i=1, n(1)
    1 x(i) = x(i)**3
"
cubefn <- cfunction(signature(n="integer", x="numeric"), code,
  convention=".Fortran")
code(cubefn)

cubefn(n, x)$x

## Not run: 
# The following code is exempted from the automated tests of example code, as
# it writes to the users home directory.
# The following writes the DLL, e.g. cubefn.so on Linux/Unix or cubefn.dll
# on Windows
moveDLL(cubefn, name = "cubefn", directory = "~")
path <- file.path("~", "cubefn.rda")
writeCFunc(cubefn, path)
rm(cubefn)

# Now you can start a fresh R session and load the function
library(inline)
path <- file.path("~", "cubefn.rda")
cfn <- readCFunc(path)
cfn(3, 1:3)$x

## End(Not run)

eddelbuettel/inline documentation built on Feb. 2, 2024, 9:26 p.m.