| cxxfunction {inline} | R Documentation |
Functionality to dynamically define an R function with inlined C++ code
using the .Call calling convention.
The rcpp() wrapper sets the plugin to the “Rcpp” value
suitable for using Rcpp.
cxxfunction(sig = character(), body = character(), plugin = "default", includes = "", settings = getPlugin(plugin), ..., verbose = FALSE) rcpp(..., plugin="Rcpp")
sig |
Signature of the function. A named character vector |
body |
A character vector with C++ code to include in the body of the compiled C++ function |
plugin |
Name of the plugin to use. See |
includes |
User includes, inserted after the includes provided by the plugin. |
settings |
Result of the call to the plugin |
... |
Further arguments to the plugin |
verbose |
verbose output |
A function
## Not run:
# default plugin
fx <- cxxfunction( signature(x = "integer", y = "numeric" ) , '
return ScalarReal( INTEGER(x)[0] * REAL(y)[0] ) ;
' )
fx( 2L, 5 )
# Rcpp plugin
if( require( Rcpp ) ){
fx <- cxxfunction( signature(x = "integer", y = "numeric" ) , '
return wrap( as<int>(x) * as<double>(y) ) ;
', plugin = "Rcpp" )
fx( 2L, 5 )
## equivalent shorter form using rcpp()
fx <- rcpp(signature(x = "integer", y = "numeric"),
' return wrap( as<int>(x) * as<double>(y) ) ; ')
}
# RcppArmadillo plugin
if( require( RcppArmadillo ) ){
fx <- cxxfunction( signature(x = "integer", y = "numeric" ) , '
int dim = as<int>( x ) ;
arma::mat z = as<double>(y) * arma::eye<arma::mat>( dim, dim ) ;
return wrap( arma::accu(z) ) ;
', plugin = "RcppArmadillo" )
fx( 2L, 5 )
}
## End(Not run)