...one of the most highly
regarded and expertly designed C++ library projects in the
world.

— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards

#include <boost/math/special_functions/beta.hpp>

namespace boost{ namespace math{ template <class T1, class T2, class T3>calculated-result-typeibeta_derivative(T1 a, T2 b, T3 x); template <class T1, class T2, class T3, class Policy>calculated-result-typeibeta_derivative(T1 a, T2 b, T3 x, const Policy&); }} // namespaces

This function finds some uses in statistical distributions: it computes
the partial derivative with respect to *x* of the incomplete
beta function ibeta.

The return type of this function is computed using the *result
type calculation rules* when T1, T2 and T3 are different
types.

The final Policy argument is optional and can be used to control the behaviour of the function: how it handles errors, what level of precision to use etc. Refer to the policy documentation for more details.

Almost identical to the incomplete beta function ibeta.

This function just expose some of the internals of the incomplete beta function ibeta: refer to the documentation for that function for more information.