maxmag

eve::maxmag = {}

inlineconstexpr

Computes the maximum of the absolute value of its arguments.

Defined in Header

#include <eve/module/core.hpp>

Callable Signatures

namespace eve
{
   template< eve::value T, eve::value... Ts >
   eve::common_compatible_t<T, Ts...> maxmag(T x, Ts ... xs) noexcept;
 
}

Parameters

• x, xs... : real or complex arguments.

Return value

The elementwise element of greatest absolute value is returned.

For instance for two elements:

• If |x| > |y|, x is returned.
• If |x| < |y|, y is returned.
• Otherwise max(x, y) is returned.

For n parameters the result is computed as if this scheme was recursively used.

Note

• If any element of the inputs is a Nan, the corresponding output element is system-dependent.

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 = {0.0f, 1.0f,  1.0f, -2.0f, 2.0f,
                eve::inf(eve::as<float>()), eve::minf(eve::as<float>()), eve::nan(eve::as<float>())};
  wide_ft qf = {4.0f, 1.0f, -1.0f,  0.0f,  -3.0f,
                eve::nan(eve::as<float>()),  -eve::nan(eve::as<float>()), -2.0f};
 
  std::cout << "---- simd" << '\n'
            << "<- pf                        = " << pf << '\n'
            << "<- qf                        = " << qf << '\n'
            << "-> maxmag(pf, qf)            = " << eve::maxmag(pf, qf) << '\n';
 
  float xf = -4.0f;
  float yf = 1.0f;
 
  std::cout << "---- scalar" << '\n'
            << "<- xf                        = " << xf << '\n'
            << "<- yf                        = " << yf << '\n'
            << "-> maxmag(xf, yf)            = " << eve::maxmag(xf, yf) << '\n';
   return 0;
}

Semantic Modifiers

• Masked Call

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

  Example

  #include <eve/module/core.hpp>
  #include <eve/wide.hpp>
  #include <iostream>
   
  using wide_ft = eve::wide<float, eve::fixed<8>>;
  using eve::pedantic;
   
  int main()
  {
    wide_ft pf = {0.0f, 1.0f, -1.0f, -2.0f, 2.0f,
                  eve::inf(eve::as<float>()), eve::minf(eve::as<float>()), eve::nan(eve::as<float>())};
    wide_ft qf = {4.0f, 1.0f, -1.0f,  0.0f, eve::nan(eve::as<float>()),
                  -0.0f, eve::nan(eve::as<float>()), -2.0f};
   
   
    std::cout << "---- simd" << '\n'
              << "<- pf                      = " << pf << '\n'
              << "<- qf                      = " << qf << '\n'
              << "-> maxmag[pf <  0](pf, qf) = " << eve::maxmag[pf <  0](pf, qf) << '\n';
    return 0;
  }

• eve::pedantic, eve::numeric

  The behaviour of d(eve::maxmag)(x, y) (where d is one of these two decorators is identical except that if |x| == |y|, d(max) is used.

  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 = {0.0f, 1.0f,  1.0f, -2.0f, 2.0f,
                  eve::inf(eve::as<float>()), eve::minf(eve::as<float>()), eve::nan(eve::as<float>())};
    wide_ft qf = {4.0f, 1.0f, -1.0f,  0.0f,  -3.0f,
                  eve::nan(eve::as<float>()),  -eve::nan(eve::as<float>()), -2.0f};
   
    std::cout << "---- simd" << '\n'
              << "<- pf                        = " << pf << '\n'
              << "<- qf                        = " << qf << '\n'
              << "-> pedantic(maxmag)(pf, qf) = " << eve::pedantic(eve::maxmag)(pf, qf) << '\n'
              << "-> numeric(maxmag)(pf, qf)  = " << eve::numeric(eve::maxmag)(pf, qf) << '\n';
     return 0;
  }