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// -*- mode: C++; c-indent-level: 4; c-basic-offset: 4; tab-width: 8 -*-
// this version is between the Rcpp_New_ptr and the Rcpp_New_std version
// test elapsed relative user.self sys.self
// 5 Rcpp_New_ptr(REPS, a, b) 0.214 1.000000 0.213 0.001
// 7 Rcpp_New_std_2(REPS, a, b) 0.223 1.042056 0.216 0.006
// 4 Rcpp_New_std(REPS, a, b) 0.524 2.448598 0.523 0.001
//
// so there is some overhead due to creating Vec objects and indexing them
// but much less than when we index the NumericVector
#include <Rcpp.h>
class Vec {
public:
Vec( double* data_ ) : data(data_){}
inline double& operator[]( int i){ return data[i] ; }
private:
double* data ;
} ;
RcppExport SEXP convolve8cpp(SEXP a, SEXP b){
Rcpp::NumericVector xa(a);
Rcpp::NumericVector xb(b);
int n_xa = xa.size() ;
int n_xb = xb.size() ;
int nab = n_xa + n_xb - 1;
Rcpp::NumericVector xab(nab);
Vec vab(xab.begin()), va(xa.begin()), vb(xb.begin()) ;
for (int i = 0; i < n_xa; i++)
for (int j = 0; j < n_xb; j++)
vab[i + j] += va[i] * vb[j];
return xab ;
}
#include "loopmacro.h"
LOOPMACRO_CPP(convolve8cpp)
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