using 'simd::accumulate' with templated functor

Author: kevinushey

examples/boost-simd-accumulate.cpp

@@ -0,0 +1,33 @@
+// [[Rcpp::depends(RcppParallel)]]
+#include <RcppParallel.h>
+#include <Rcpp.h>
+using namespace Rcpp;
+
+#include <boost/simd/sdk/simd/algorithm.hpp>
+
+struct plus
+{
+   template <class T>
+   T operator()(const T& lhs, const T& rhs) const
+   {
+      return lhs + rhs;
+   }
+};
+
+// [[Rcpp::export]]
+double simd_sum(NumericVector x)
+{
+   return boost::simd::accumulate(
+      x.begin(),
+      x.end(),
+      0.0,
+      plus()
+   );
+}
+
+/***R
+n <- 1024 * 1000
+data <- rnorm(n)
+simd_sum(data)
+microbenchmark(R = sum(data), simd = simd_sum(data))
+*/