From 55e2b17b020e236f6d4b3bac541c08ae5d715aee Mon Sep 17 00:00:00 2001
From: Jacob Hass <jacobhass8@gmail.com>
Date: Fri, 2 Jan 2026 10:29:52 -0800
Subject: [PATCH] Added boost tuple support

---
 .../math/distributions/non_central_f.hpp      | 24 +++++++++++++++++--
 test/test_nc_f.cpp                            |  2 ++
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/include/boost/math/distributions/non_central_f.hpp b/include/boost/math/distributions/non_central_f.hpp
index 5013c2408..63736a2b5 100644
--- a/include/boost/math/distributions/non_central_f.hpp
+++ b/include/boost/math/distributions/non_central_f.hpp
@@ -17,6 +17,7 @@
 #include <boost/math/distributions/detail/generic_mode.hpp>
 #include <boost/math/special_functions/pow.hpp>
 #include <boost/math/policies/policy.hpp>
+#include <boost/math/distributions/complement.hpp> // complements
 
 namespace boost
 {
@@ -24,8 +25,6 @@ namespace boost
    {
       namespace detail
       {
-         /* Need to rewrite this according to `find_non_centrality` in 
-         non_central_chi_squared.hpp */
          template <class RealType, class Policy>
          struct non_centrality_finder_f
          {
@@ -128,6 +127,27 @@ namespace boost
                result,
                function);
          }
+         template <class A, class B, class C, class D>
+         BOOST_MATH_GPU_ENABLED static RealType find_non_centrality(const complemented4_type<A,B,C, D>& c)
+         {
+            constexpr auto function = "non_central_f_distribution<%1%>::find_non_centrality";
+            typedef typename policies::evaluation<RealType, Policy>::type eval_type;
+            typedef typename policies::normalise<
+               Policy,
+               policies::promote_float<false>,
+               policies::promote_double<false>,
+               policies::discrete_quantile<>,
+               policies::assert_undefined<> >::type forwarding_policy;
+            eval_type result = detail::find_non_centrality_f(
+               static_cast<eval_type>(c.dist),
+               static_cast<eval_type>(c.param1),
+               static_cast<eval_type>(c.param2),
+               static_cast<eval_type>(c.param3),
+               forwarding_policy());
+            return policies::checked_narrowing_cast<RealType, forwarding_policy>(
+               result,
+               function);
+         }
       private:
          // Data member, initialized by constructor.
          RealType v1;   // alpha.
diff --git a/test/test_nc_f.cpp b/test/test_nc_f.cpp
index 22cc667d5..064e9eb88 100644
--- a/test/test_nc_f.cpp
+++ b/test/test_nc_f.cpp
@@ -143,6 +143,8 @@ void test_spot(
             quantile(complement(dist, Q)), x, tol * 10);
       BOOST_CHECK_CLOSE(
             dist.find_non_centrality(a, b, P, x), ncp, tol * 10);
+      BOOST_CHECK_CLOSE(
+            dist.find_non_centrality(boost::math::complement(a, b, P, x)), ncp, tol * 10);
    }
    if(boost::math::tools::digits<RealType>() > 50)
    {