gamma_p_inv

eve::gamma_p_inv = functor<gamma_p_inv_t>

inlineconstexpr

Header file

#include <eve/module/special.hpp>

Callable Signatures

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

Parameters

• x, y: floating value.
• c: Conditional expression masking the operation.
• m: Logical value masking the operation.

Return value

1. The value of the inverse of the normalized lower incomplete \(\Gamma\) function relative to the first parameter is returned.
2. The operation is performed conditionnaly.

External references

• Wikipedia: Incomplete gamma function
• DLMF

Example

// revision 1
#include <eve/module/special.hpp>
#include <iostream>
 
int main()
{
 
  eve::wide wk = {1.0e-3, 0.3, 0.75, 5.5};
  eve::wide wp = {10.0, 0.5, 20.7, 1.0};
 
  std::cout << "<- wk                             = " << wk << "\n";
  std::cout << "<- wp                             = " << wp << "\n";
 
  std::cout << "-> gamma_p(wk, wp)                = " << eve::gamma_p(wk, wp) << "\n";
  std::cout << "-> gamma_p[ignore_last(2)](wk, wp)= " << eve::gamma_p[eve::ignore_last(2)](wk, wp) << "\n";
  std::cout << "-> gamma_p[wk > 0.5](wk, wp)      = " << eve::gamma_p[wk > 0.5](wk, wp) << "\n";
}