ulpdist

auto eve::ulpdist = functor<ulpdist_t>

inlineconstexpr

Header file

#include <eve/module/core.hpp>

Callable Signatures

namespace eve
{
   // Regular overload
   constexpr auto ulpdist(floating_value auto x, floating_value auto y)                          noexcept; // 1
 
   // Lanes masking
   constexpr auto ulpdist[conditional_expr auto c][floating_value auto x, floating_value auto y) noexcept; // 3
   constexpr auto ulpdist[logical_value auto m](floating_value auto x, floating_value auto y)    noexcept; // 3
}

Parameters

• x, y: arguments.
• c: Conditional expression masking the operation.
• m: Logical value masking the operation.

Return value

1. Computes elementwise the 'units in the last place' distance between x and y.
   • if is_ordered(x,y), nb_values(x,y)/2.0 is returned
   • otherwise a Nan is returned
2. The operation is performed conditionnaly.

Example

// revision 0
#include <eve/module/core.hpp>
#include <iostream>
 
int main()
{
  eve::wide wf0{0.0, 1.0, 2.0, 3.0, -1.0, -2.0, -3.0, -4.0};
  eve::wide wf1{0.0, -4.0, 1.0, -1.0, 2.0, -2.0, 3.0, -3.0};
 
  std::cout << "<- wf0                               = " << wf0 << "\n";
  std::cout << "<- wf1                               = " << wf1 << "\n";
                                                     
  std::cout << "-> ulpdist(wf0, wf1)                 = " << eve::ulpdist(wf0, wf1) << "\n";
  std::cout << "-> ulpdist[ignore_last(2)](wf0, wf1) = " << eve::ulpdist[eve::ignore_last(2)](wf0, wf1) << "\n";
  std::cout << "-> ulpdist[wf0 != -2.0f](wf0, wf1)   = " << eve::ulpdist[wf0 != -2.0f](wf0, wf1) << "\n";
}