Add magnitude_sq function to support non-f32

Signed-off-by: Markus Mayer <[email protected]>

src/float.rs

@@ -226,7 +226,7 @@ impl F32 {
     /// Is this floating point value even?
     fn is_even(&self) -> bool {
         // any floating point value that doesn't fit in an i32 range is even,
-        // and will loose 1's digit precision at exp values of 23+
+        // and will lose 1's digit precision at exp values of 23+
         if self.extract_exponent_value() >= 31 {
             true
         } else {

src/vector.rs

@@ -59,6 +59,14 @@ where
         differences.map(|n| n * n).sum::<f32>().sqrt()
     }
 
+    /// Compute the squared magnitude of a vector
+    fn magnitude_sq(self) -> C
+    where
+        C: core::iter::Sum,
+    {
+        self.iter().map(|n| n * n).sum()
+    }
+
     /// Compute the magnitude of a vector
     fn magnitude(self) -> f32
     where
@@ -73,3 +81,19 @@ where
             .sqrt()
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn magnitude_sq() {
+        let vec = Vector3d {
+            x: 3.0,
+            y: 4.0,
+            z: 5.0,
+        };
+        let mag = vec.magnitude_sq();
+        assert_eq!(mag, 3.0 * 3.0 + 4.0 * 4.0 + 5.0 * 5.0);
+    }
+}