std::comp_ellint_2, std::comp_ellint_2f, std::comp_ellint_2l
double comp_ellint_2( double arg ); double comp_ellint_2( float arg ); |
(1) | |
double comp_ellint_2( IntegralType arg ); |
(2) | |
As all special functions, comp_ellint_2
is only guaranteed to be available in <cmath>
if __STDCPP_MATH_SPEC_FUNCS__
is defined by the implementation to a value at least 201003L and if the user defines __STDCPP_WANT_MATH_SPEC_FUNCS__
before including any standard library headers.
Parameters
arg | - | value of a floating-point or integral type |
Return value
If no errors occur, value of the complete elliptic integral of the second kind of arg
, that is ellint_2(arg,π/2), is returned.
Error handling
Errors may be reported as specified in math_errhandling
- If the argument is NaN, NaN is returned and domain error is not reported
- If |arg|>1, a domain error may occur
Notes
Implementations that do not support TR 29124 but support TR 19768, provide this function in the header tr1/cmath
and namespace std::tr1
An implementation of this function is also available in boost.math
Example
(works as shown with gcc 6.0)
#define __STDCPP_WANT_MATH_SPEC_FUNCS__ 1 #include <cmath> #include <iostream> int main() { double hpi = std::acos(-1)/2; std::cout << "E(0) = " << std::comp_ellint_2(0) << '\n' << "π/2 = " << hpi << '\n' << "E(0.5) = " << std::comp_ellint_2(0.5) << '\n' << "E(0.5, π/2) = " << std::ellint_2(0.5, hpi) << '\n'; }
Output:
E(0) = 1.5708 π/2 = 1.5708 E(0.5) = 1.46746 E(0.5, π/2) = 1.46746
External links
Weisstein, Eric W. "Complete Elliptic Integral of the Second Kind." From MathWorld--A Wolfram Web Resource.
See also
(incomplete) elliptic integral of the second kind (function) |