/////////////////////////////////////////////////////////////////////
// = NMatrix
//
// A linear algebra library for scientific computation in Ruby.
// NMatrix is part of SciRuby.
//
// NMatrix was originally inspired by and derived from NArray, by
// Masahiro Tanaka: http://narray.rubyforge.org
//
// == Copyright Information
//
// SciRuby is Copyright (c) 2010 - 2014, Ruby Science Foundation
// NMatrix is Copyright (c) 2012 - 2014, John Woods and the Ruby Science Foundation
//
// Please see LICENSE.txt for additional copyright notices.
//
// == Contributing
//
// By contributing source code to SciRuby, you agree to be bound by
// our Contributor Agreement:
//
// * https://github.com/SciRuby/sciruby/wiki/Contributor-Agreement
//
// == swap.h
//
// BLAS level 2 swap function in native C++.
//

#ifndef SWAP_H
#define SWAP_H

namespace nm { namespace math {
// This is the old BLAS version of this function. ATLAS has an optimized version, but
// it's going to be tough to translate.
template <typename DType>
static void swap(const int N, DType* X, const int incX, DType* Y, const int incY) {
  if (N > 0) {
    int ix = 0, iy = 0;
    for (int i = 0; i < N; ++i) {
      DType temp = X[i];
      X[i]       = Y[i];
      Y[i]       = temp;

      ix += incX;
      iy += incY;
    }
  }
}

}} // end nm::math

#endif