chi

auto eve::chi = functor<chi_t>

inlineconstexpr

Defined in Header

#include <eve/module/core.hpp>

Callable Signatures

namespace eve
{
   // Regular overload
   constexpr auto chi(value auto x, value auto lo,  value auto hi)             noexcept; // 1
   constexpr auto chi(value auto x, auto belongs)                              noexcept; // 2
 
   // Lanes masking
   constexpr auto chi[conditional_expr auto c](/*any of the above overloads*/) noexcept; // 3
   constexpr auto chi[logical_value auto m](/*any of the above overloads*/)    noexcept; // 3
}

Parameters

• x: value to chi.
• lo, hi: the boundary values of the interval.
• belongs: predicate function
• c: Conditional expression masking the operation.
• m: Logical value masking the operation.

Return value

1. Each element of the result contains:
   • 0, if x is less than lo. or if hi is strictly less than x.
   • 1 otherwise. 2 1 in the type of x if belongs(x) evaluate to true else 0.
2. The operation is performed conditionnaly.

Note

If any lo is not less or equal to the corresponding hi the routine asserts.

External references

• wikipedia

Example

#include <eve/module/core.hpp>
#include <eve/wide.hpp>
#include <iostream>
 
int main()
{
  eve::wide x = {2.0, -3.0, 0.1, 4.0};
  eve::wide lo = {3.0, -4.0, -10.0, 0.0};
  eve::wide hi = {4.0, -1.0, 0.0, 5.0};
 
  auto belongs =  [](auto v) {return v > 3.0 || v == 2.0; };
 
  std::cout << " <- x                       = " << x << '\n';
  std::cout << " <- lo                      = " << lo << '\n';
  std::cout << " <- hi                      = " << hi << '\n';
  std::cout << " -> chi(x, belongs)         = " << eve::chi(x, belongs) << '\n';
  std::cout << " -> chi(x, lo, hi)          = " << eve::chi(x, lo, hi) << '\n';
  std::cout << " -> chi[x > -2](x, lo, hi)  = " << eve::chi[x > -2](x, lo, hi) << '\n';
}