diff --git a/fixed_wide_vectors/src/macros/matrix.rs b/fixed_wide_vectors/src/macros/matrix.rs
index 0c1c371..cde4330 100644
--- a/fixed_wide_vectors/src/macros/matrix.rs
+++ b/fixed_wide_vectors/src/macros/matrix.rs
@@ -38,7 +38,7 @@ macro_rules! impl_matrix {
 			where
 				T:core::ops::Mul<U,Output=V>+Copy,
 				V:core::iter::Sum,
-				U:Clone,
+				U:Copy,
 			{
 				let mut array_of_iterators=rhs.array.map(|axis|axis.into_iter().cycle());
 				Matrix{
@@ -46,11 +46,9 @@ macro_rules! impl_matrix {
 						core::array::from_fn(|_|
 							// axis dot product with transposed rhs array
 							axis.iter().zip(
-								array_of_iterators.each_mut().map(|iter|
-									iter.next().unwrap()
-								)
-							).map(|(&a,b)|
-								a*b
+								array_of_iterators.iter_mut()
+							).map(|(&lhs_value,rhs_iter)|
+								lhs_value*rhs_iter.next().unwrap()
 							).sum()
 						)
 					)