diff -r bd924d62d952 -r a0db98c16ab5 src/bisection_tree/either.rs
--- a/src/bisection_tree/either.rs	Wed Nov 06 15:34:17 2024 -0500
+++ b/src/bisection_tree/either.rs	Sat Nov 09 20:36:23 2024 -0500
@@ -191,9 +191,9 @@
 }
 
 impl<F, S1, S2, X> Differentiable<X> for EitherSupport<S1, S2>
-where S1 : Differentiable<X, Output=F>,
-      S2 : Differentiable<X, Output=F> {
-    type Output = F;
+where S1 : Differentiable<X, Derivative=F>,
+      S2 : Differentiable<X, Derivative=F> {
+    type Derivative = F;
     #[inline]
     fn differential(&self, x : X) -> F {
         match self {