Mercurial > repos > alg_tools / changeset

--- a/src/euclidean.rs	Fri Nov 28 14:01:14 2025 -0500
+++ b/src/euclidean.rs	Mon Dec 01 19:50:58 2025 -0500
@@ -4,7 +4,7 @@
 
 use crate::instance::Instance;
 use crate::linops::{VectorSpace, AXPY};
-use crate::norms::Reflexive;
+use crate::norms::{HasDual, Norm, Normed, Reflexive, L2};
 use crate::types::*;
 
 pub mod wrap;
@@ -92,3 +92,74 @@
     /// Returns the origin
     fn origin() -> <Self as Euclidean<F>>::PrincipalE;
 }
+
+macro_rules! scalar_euclidean {
+    ($f:ident) => {
+        impl VectorSpace for $f {
+            type Field = $f;
+            type PrincipalV = $f;
+
+            #[inline]
+            fn similar_origin(&self) -> Self::PrincipalV {
+                0.0
+            }
+        }
+        impl AXPY for $f {
+            #[inline]
+            fn axpy<I: Instance<$f>>(&mut self, α: $f, x: I, β: $f) {
+                *self = β * *self + α * x.own()
+            }
+
+            #[inline]
+            fn set_zero(&mut self) {
+                *self = 0.0
+            }
+        }
+
+        impl Norm<L2, $f> for $f {
+            fn norm(&self, _p: L2) -> $f {
+                self.abs()
+            }
+        }
+
+        impl Normed<$f> for $f {
+            type NormExp = L2;
+
+            fn norm_exponent(&self) -> Self::NormExp {
+                L2
+            }
+        }
+
+        impl HasDual<$f> for $f {
+            type DualSpace = $f;
+
+            #[inline]
+            fn dual_origin(&self) -> $f {
+                0.0
+            }
+        }
+
+        impl Euclidean<$f> for $f {
+            type PrincipalE = $f;
+
+            #[inline]
+            fn dot<I: Instance<Self>>(&self, other: I) -> $f {
+                *self * other.own()
+            }
+
+            #[inline]
+            fn norm2_squared(&self) -> $f {
+                *self * *self
+            }
+
+            #[inline]
+            fn dist2_squared<I: Instance<Self>>(&self, y: I) -> $f {
+                let d = *self - y.own();
+                d * d
+            }
+        }
+    };
+}
+
+scalar_euclidean!(f64);
+scalar_euclidean!(f32);