erfc_inv

eve::erfc_inv = functor<erfc_inv_t>

inlineconstexpr

Header file

#include <eve/module/special.hpp>

Callable Signatures

namespace eve
{
   // Regular overload
   constexpr auto erfc_inv(floating_value auto x)                          noexcept; // 1
 
   // Lanes masking
   constexpr auto erfc_inv[conditional_expr auto c](floating_value auto x) noexcept; // 2
   constexpr auto erfc_inv[logical_value auto m](floating_value auto x)    noexcept; // 2
}

Parameters

• x: real floating argument. Must be in interval \([0, 2]\) else nan is returned.
• c: Conditional expression masking the operation.
• m: Logical value masking the operation.

Return value

1. The value of the inverse complementary error function is returned. In particular:
   • If the argument is \(\pm0\), \(1\) is returned.
   • If the argument is \(2\), \(-\infty\) is returned.
   • If the argument is \(0\), \(\infty\) is returned.
   • If the argument is NaN, NaN is returned.

External references

• C++ standard reference: erf
• Wolfram MathWorld: Erf
• DLMF: Error Functions
• Wikipedia: Error Function

Example

// revision 1
#include <eve/module/special.hpp>
#include <iostream>
 
int main()
{
  eve::wide<float> wf([](auto i, auto c)->float{ return 2*(i-c/2);});
 
  std::cout << "<- wf = " << wf << "\n";
 
  std::cout << "-> erfc_inv(wf)                = " << eve::erfc_inv(wf) << "\n";
  std::cout << "-> erfc_inv[ignore_last(2)](wf)= " << eve::erfc_inv[eve::ignore_last(2)](wf) << "\n";
  std::cout << "-> erfc_inv[wf != -2.0f](wf)   = " << eve::erfc_inv[wf != -2.0f](wf) << "\n";
}