cpp/experimental/special functions/comp ellint 1

@1@ Computes the complete elliptic integral of the first kind of. @4@ A set of overloads or a function template accepting an argument of any integral type. Equivalent to after casting the argument to.

Return value
If no errors occur, value of the complete elliptic integral of the first kind of, that is ellint_1(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