R bindings for the xtensor C++ multi-dimensional array library.

• xtensor is a C++ library for multi-dimensional arrays enabling numpy-style broadcasting and lazy computing.

• xtensor-r enables inplace use of R arrays in C++ with all the benefits from xtensor

  • C++ universal functions and broadcasting
  • STL - compliant APIs.
  • A broad coverage of numpy APIs (see the numpy to xtensor cheat sheet).

xtensor-r can be used either to author C++ extensions for R with Rcpp, or applications that embed the R interpreter with RInside.

Example

#include <numeric>                    // Standard library import for std::accumulate
#define STRICT_R_HEADERS              // Otherwise a PI macro is defined in R
#include "xtensor/xmath.hpp"          // xtensor import for the C++ universal functions
#include "xtensor-r/rarray.hpp"       // R bindings

#include <Rcpp.h>

using namespace Rcpp;

// [[Rcpp::plugins(cpp14)]]

// [[Rcpp::export]]
double sum_of_sines(xt::rarray<double>& m)
{
    auto sines = xt::sin(m);  // sines does not actually hold values.
    return std::accumulate(sines.cbegin(), sines.cend(), 0.0);
}

v <- matrix(0:14, nrow=3, ncol=5)
s <- sum_of_sines(v)
s

# prints 1.2853996391883833

Installation

From conda-forge

Xtensor.R is available on conda-forge, it can be installed with conda, mamba, and rhumba.

mamba install r-xtensor -c conda-forge

From CRAN

Xtensor.R is available on CRAN (The Comprehensive R Archive Network).

install.packages("xtensor")

From the GitHub repository

Xtensor.R can be installed from GitHub directly using devtools

devtools::install_github("QuantStack/Xtensor.R", ref="package")

Documentation

To get started with using Xtensor.R, check out the documentation at

http://xtensor-r.readthedocs.io/

Dependencies

xtensor-r depends on the xtensor and Rcpp libraries

License

We use a shared copyright model that enables all contributors to maintain the copyright on their contributions.

This software is licensed under the BSD-3-Clause license. See the LICENSE file for details.