Merge pull request #509 from jturner314/dimension-zeros

Rename zero_index_with_ndim -> zeros, make it public, and remove zero_index

Author: jturner314

src/dimension/dimension_trait.rs

@@ -151,20 +151,13 @@ pub trait Dimension : Clone + Eq + Debug + Send + Sync + Default +
         strides
     }
 
-    #[doc(hidden)]
-    // Return an index of same dimensionality
-    fn zero_index(&self) -> Self {
-        Self::default()
-    }
-
-    #[doc(hidden)]
-    /// Return an index of same type and with the specified dimensionality.
+    /// Creates a dimension of all zeros with the specified ndim.
     ///
     /// This method is useful for generalizing over fixed-size and
     /// variable-size dimension representations.
     ///
     /// **Panics** if `Self` has a fixed size that is not `ndim`.
-    fn zero_index_with_ndim(ndim: usize) -> Self;
+    fn zeros(ndim: usize) -> Self;
 
     #[doc(hidden)]
     #[inline]
@@ -174,11 +167,7 @@ pub trait Dimension : Clone + Eq + Debug + Send + Sync + Default +
                 return None;
             }
         }
-        let mut index = self.clone();
-        for rr in index.slice_mut().iter_mut() {
-            *rr = 0;
-        }
-        Some(index)
+        Some(Self::zeros(self.ndim()))
     }
 
     #[doc(hidden)]
@@ -381,7 +370,7 @@ impl Dimension for Dim<[Ix; 0]> {
     #[inline]
     fn into_pattern(self) -> Self::Pattern { }
     #[inline]
-    fn zero_index_with_ndim(ndim: usize) -> Self {
+    fn zeros(ndim: usize) -> Self {
         assert_eq!(ndim, 0);
         Self::default()
     }
@@ -417,7 +406,7 @@ impl Dimension for Dim<[Ix; 1]> {
         get!(&self, 0)
     }
     #[inline]
-    fn zero_index_with_ndim(ndim: usize) -> Self {
+    fn zeros(ndim: usize) -> Self {
         assert_eq!(ndim, 1);
         Self::default()
     }
@@ -511,7 +500,7 @@ impl Dimension for Dim<[Ix; 2]> {
     #[inline]
     fn slice_mut(&mut self) -> &mut [Ix] { self.ixm() }
     #[inline]
-    fn zero_index_with_ndim(ndim: usize) -> Self {
+    fn zeros(ndim: usize) -> Self {
         assert_eq!(ndim, 2);
         Self::default()
     }
@@ -656,7 +645,7 @@ impl Dimension for Dim<[Ix; 3]> {
     }
 
     #[inline]
-    fn zero_index_with_ndim(ndim: usize) -> Self {
+    fn zeros(ndim: usize) -> Self {
         assert_eq!(ndim, 3);
         Self::default()
     }
@@ -765,7 +754,7 @@ macro_rules! large_dim {
             #[inline]
             fn slice_mut(&mut self) -> &mut [Ix] { self.ixm() }
             #[inline]
-            fn zero_index_with_ndim(ndim: usize) -> Self {
+            fn zeros(ndim: usize) -> Self {
                 assert_eq!(ndim, $n);
                 Self::default()
             }
@@ -818,12 +807,7 @@ impl Dimension for IxDyn
     }
 
     #[inline]
-    fn zero_index(&self) -> Self {
-        IxDyn::zeros(self.ndim())
-    }
-
-    #[inline]
-    fn zero_index_with_ndim(ndim: usize) -> Self {
+    fn zeros(ndim: usize) -> Self {
         IxDyn::zeros(ndim)
     }
 

src/impl_methods.rs

@@ -318,8 +318,8 @@ impl<A, S, D> ArrayBase<S, D> where S: Data<Elem=A>, D: Dimension
 
         // Copy the dim and strides that remain after removing the subview axes.
         let out_ndim = info.out_ndim();
-        let mut new_dim = Do::zero_index_with_ndim(out_ndim);
-        let mut new_strides = Do::zero_index_with_ndim(out_ndim);
+        let mut new_dim = Do::zeros(out_ndim);
+        let mut new_strides = Do::zeros(out_ndim);
         izip!(self.dim.slice(), self.strides.slice(), indices)
             .filter_map(|(d, s, slice_or_index)| match slice_or_index {
                 &SliceOrIndex::Slice {..} => Some((d, s)),
@@ -1401,7 +1401,7 @@ impl<A, S, D> ArrayBase<S, D> where S: Data<Elem=A>, D: Dimension
     {
         let axes = axes.into_dimension();
         // Ensure that each axis is used exactly once.
-        let mut usage_counts = D::zero_index_with_ndim(self.ndim());
+        let mut usage_counts = D::zeros(self.ndim());
         for axis in axes.slice() {
             usage_counts[*axis] += 1;
         }
@@ -1410,7 +1410,7 @@ impl<A, S, D> ArrayBase<S, D> where S: Data<Elem=A>, D: Dimension
         }
         // Determine the new shape and strides.
         let mut new_dim = usage_counts; // reuse to avoid an allocation
-        let mut new_strides = D::zero_index_with_ndim(self.ndim());
+        let mut new_strides = D::zeros(self.ndim());
         {
             let dim = self.dim.slice();
             let strides = self.strides.slice();

src/indexes.rs

@@ -31,7 +31,7 @@ pub fn indices<E>(shape: E) -> Indices<E::Dim>
 {
     let dim = shape.into_dimension();
     Indices {
-        start: dim.zero_index(),
+        start: E::Dim::zeros(dim.ndim()),
         dim: dim,
     }
 }
@@ -210,7 +210,7 @@ pub fn indices_iter_f<E>(shape: E) -> IndicesIterF<E::Dim>
     where E: IntoDimension,
 {
     let dim = shape.into_dimension();
-    let zero = dim.zero_index();
+    let zero = E::Dim::zeros(dim.ndim());
     IndicesIterF {
         has_remaining: dim.size_checked() != Some(0),
         index: zero,