Submit promoted power as parameter rather than intermediate value

mborland · mborland · commit 5998fec826f9 · 2025-08-13T10:58:21.000+02:00
diff --git a/include/boost/math/distributions/logistic.hpp b/include/boost/math/distributions/logistic.hpp
@@ -147,8 +147,9 @@ namespace boost { namespace math {
           return result;
        }
 
-       RealType power = (x - location) / scale;
-       return logistic_sigmoid(power, Policy());
+       using promoted_real_type = typename policies::evaluation<RealType, Policy>::type;
+       promoted_real_type power = (static_cast<promoted_real_type>(x) - static_cast<promoted_real_type>(location)) / static_cast<promoted_real_type>(scale);
+       return logistic_sigmoid<false>(power, Policy());
     }
 
     template <class RealType, class Policy>
@@ -248,8 +249,10 @@ namespace boost { namespace math {
        {
           return result;
        }
-       RealType power = (location - x) / scale;
-       return logistic_sigmoid(power, Policy());
+
+       using promoted_real_type = typename policies::evaluation<RealType, Policy>::type;
+       promoted_real_type power = (static_cast<promoted_real_type>(location) - static_cast<promoted_real_type>(x)) / static_cast<promoted_real_type>(scale);
+       return logistic_sigmoid<false>(power, Policy());
     } 
 
     template <class RealType, class Policy>

Original file line number	Diff line number	Diff line change
`@@ -147,8 +147,9 @@ namespace boost { namespace math {`
`147`	`147`	`return result;`
`148`	`148`	`}`
`149`	`149`
`150`		`- RealType power = (x - location) / scale;`
`151`		`- return logistic_sigmoid(power, Policy());`
	`150`	`+ using promoted_real_type = typename policies::evaluation<RealType, Policy>::type;`
	`151`	`+ promoted_real_type power = (static_cast<promoted_real_type>(x) - static_cast<promoted_real_type>(location)) / static_cast<promoted_real_type>(scale);`
	`152`	`+ return logistic_sigmoid<false>(power, Policy());`
`152`	`153`	`}`
`153`	`154`
`154`	`155`	`template <class RealType, class Policy>`
`@@ -248,8 +249,10 @@ namespace boost { namespace math {`
`248`	`249`	`{`
`249`	`250`	`return result;`
`250`	`251`	`}`
`251`		`- RealType power = (location - x) / scale;`
`252`		`- return logistic_sigmoid(power, Policy());`
	`252`	`+`
	`253`	`+ using promoted_real_type = typename policies::evaluation<RealType, Policy>::type;`
	`254`	`+ promoted_real_type power = (static_cast<promoted_real_type>(location) - static_cast<promoted_real_type>(x)) / static_cast<promoted_real_type>(scale);`
	`255`	`+ return logistic_sigmoid<false>(power, Policy());`
`253`	`256`	`}`
`254`	`257`
`255`	`258`	`template <class RealType, class Policy>`