Rcpp Integration

Introduction

Rcpp integrates C++ code into R for performance. It speeds up computationally intensive operations.

Basic Rcpp

library(Rcpp)

# Create C++ function
cppFunction('
int add(int x, int y) {
  return x + y;
}
')

add(2, 3)

Using Vectors

cppFunction('
NumericVector squaring(NumericVector x) {
  return x * x;
}
')

SourceCpp

// In file: functions.cpp
#include <Rcpp.h>
using namespace Rcpp;

// [[Rcpp::export]]
double sum_cpp(NumericVector x) {
  return sum(x);
}
')

library(Rcpp)
sourceCpp("functions.cpp")

Performance Comparison

library(microbenchmark)
microbenchmark(
  R = sum(x),
  Cpp = sum_cpp(x)
)

Summary

Rcpp provides C++ speed in R. Use it for performance-critical code.