nearest

eve::nearest = {}

inlineconstexpr

Computes the nearest integer to the input.

Defined in Header

#include <eve/module/core.hpp>

Callable Signatures

namespace eve
{
   template< eve::value T >
   T nearest(T x) noexcept;
}

Parameters

• x : real or complex argument.

Return value

Computes elementwise the integer nearest to x.

If x is an exact half-integer the rounding is made to the nearest even integer.

The standard proposes 4 rounding modes namely: FE_TONEAREST, FE_DOWNWARD, FE_UPWARD, FE_TOWARDZERO. This function object implements the FE_TONEAREST version.

For complex inputs the nearest operation is applied to both real and imaginary parts.

Example

#include <eve/module/core.hpp>
#include <eve/wide.hpp>
#include <iostream>
 
using wide_ft = eve::wide<float, eve::fixed<8>>;
 
int main()
{
  wide_ft pf = {-1.0f, -1.3f, -1.5f, -1.7f, 2.0f, 2.3f, 2.5f, 2.7f};
 
  std::cout << "---- simd" << '\n'
            << "<- pf                = " << pf << '\n'
            << "-> nearest(pf)       = " << eve::nearest(pf) << '\n';
 
  float xf = -32.768f;
 
  std::cout << "---- scalar" << '\n'
            << "<- xf          = " << xf << '\n'
            << "-> nearest(xf) = " << eve::nearest(xf) << '\n';
  return 0;
}

Semantic Modifiers

• Masked Call

  The call eve;nearest[mask](x) provides a masked version of eve::nearest which is equivalent to if_else (mask, nearest(x), x).

  Example

  #include <eve/module/core.hpp>
  #include <eve/wide.hpp>
  #include <iostream>
   
  using wide_ft = eve::wide<float, eve::fixed<8>>;
   
  int main()
  {
    wide_ft pf = {-1.0f, -1.3f, -1.5f, -1.7f, 2.0f, 2.3f, 2.5f, 2.7f};
   
    std::cout << "---- simd" << '\n'
              << "<- pf                = " << pf << '\n'
              << "-> nearest[pf > -1](pf)       = " << eve::nearest[pf > -1](pf) << '\n';
    return 0;
  }