Implement realnum::rand (#251)

Co-authored-by: Luis Moreno <morenol@users.noreply.github.com>
Co-authored-by: Lorenzo <tunedconsulting@gmail.com>

* Implement rand. Use the new derive [#default]
* Use custom range
* Use range seed
* Bump version
* Add array length checks for

src/neighbors/mod.rs

@@ -49,20 +49,15 @@ pub type KNNAlgorithmName = crate::algorithm::neighbour::KNNAlgorithmName;
 
 /// Weight function that is used to determine estimated value.
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Default)]
 pub enum KNNWeightFunction {
     /// All k nearest points are weighted equally
+    #[default]
     Uniform,
     /// k nearest points are weighted by the inverse of their distance. Closer neighbors will have a greater influence than neighbors which are further away.
     Distance,
 }
 
-impl Default for KNNWeightFunction {
-    fn default() -> Self {
-        KNNWeightFunction::Uniform
-    }
-}
-
 impl KNNWeightFunction {
     fn calc_weights(&self, distances: Vec<f64>) -> std::vec::Vec<f64> {
         match *self {