two_add

auto eve::two_add = functor<two_add_t>

inlineconstexpr

Header file

#include <eve/module/core.hpp>

Callable Signatures

namespace eve
{
   // Regular overload
   constexpr auto two_add(floating_value auto x, floating_value auto y)            noexcept; // 1
   constexpr auto two_add[raw](floating_value auto x, floating_value auto y)       noexcept; // 2
 
   // Semantic options
   constexpr auto two_add[pedantic](floating_value auto x, floating_value auto y)  noexcept; // 3
}

Parameters

• x, y: floating-point arguments.

Return value

Computes elementwise a pair of values [a,e] such that:

• a is x+y
• e is a value such that a \(\oplus\)e is equal to x \(\oplus\)y, where \(\oplus\) adds its two parameters with infinite precision.

Classical algorithm, always valid.

1. 'Fast' algorithm, valid only if |x| < |y|.
2. Handles overflow.

External references

• On the Computation of Correctly-Rounded Sums

Example

// revision 1
#include <eve/module/core.hpp>
#include <iostream>
#include <iomanip>
 
int main()
{
  eve::wide wf0 = {3.0f, 2.5f, -32.7f, 1.0f};
  eve::wide wf1 = {4.2f, 1.5f, -100.834f, eve::eps(eve::as<float>())/2};
 
  std::cout << "<- wf0               = " << wf0 << "\n";
  std::cout << "<- wf1               = " << wf1 << "\n";
  std::cout << std::setprecision(20);
  std::cout << "-> two_add(wf0, wf1)      = " << eve::two_add(wf0, wf1) << "\n";
  std::cout << "-> two_add[raw](wf0, wf1) = " << eve::two_add[eve::raw](wf0, wf1) << "\n";
}