is_positive

eve::is_positive = functor<is_positive_t>

inlineconstexpr

Header file

#include <eve/module/core.hpp>

Callable Signatures

namespace eve
{
   constexpr auto is_positive(value auto x)                          noexcept; // 1
 
   // Lanes masking
   constexpr auto is_positive[conditional_expr auto c](value auto x) noexcept; // 2
   constexpr auto is_positive[logical_value auto m](value auto x)    noexcept; // 2
}

Parameters

• x: argument.
• c: Conditional expression masking the operation.
• m: Logical value masking the operation.

Return value

1. this function coincides with is_gtz on integral values, but The call is_positive(x) elementwise returns true if and only if the bit of sign (most significant bit) is not set.
2. The operation is performed conditionnaly.

Note

this function coincides with is_gez on integral real values, but for floating values T, is_positive(mzero<T>) is false and if x is a Nan the result depends of the bit of sign of x which can be out of control although not undefined.

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 wi0{0, 1, 2, 3, -1, -2, -3, -4};
  eve::wide wu0{0u, 1u, 2u, 3u, 4u, 5u, 6u, 7u};
 
  std::cout << "<- wf0                              = " << wf0 << "\n";
  std::cout << "<- wi0                              = " << wi0 << "\n";
  std::cout << "<- wu0                              = " << wu0 << "\n";
                                                    
  std::cout << "-> is_positive(wf0)                 = " << eve::is_positive(wf0) << "\n";
  std::cout << "-> is_positive[ignore_last(2)](wf0) = " << eve::is_positive[eve::ignore_last(2)](wf0) << "\n";
  std::cout << "-> is_positive[wf0 != 0](wf0)       = " << eve::is_positive[wf0 != 0](wf0) << "\n";
  std::cout << "-> is_positive(wu0)                 = " << eve::is_positive(wu0) << "\n";
  std::cout << "-> is_positive[ignore_last(2)](wu0) = " << eve::is_positive[eve::ignore_last(2)](wu0) << "\n";
  std::cout << "-> is_positive[wu0 != 0](wu0)       = " << eve::is_positive[wu0 != 0](wu0) << "\n";
  std::cout << "-> is_positive(wi0)                 = " << eve::is_positive(wi0) << "\n";
  std::cout << "-> is_positive[ignore_last(2)](wi0) = " << eve::is_positive[eve::ignore_last(2)](wi0) << "\n";
  std::cout << "-> is_positive[wi0 != 0](wi0)       = " << eve::is_positive[wi0 != 0](wi0) << "\n";
}