ixdyn: Implement zero-dim indexing for IxDyn

(Enables indexing a zero dimensional dynamic dimension array using
array[[]], array[()], array[Ix0()])

Author: bluss

src/dimension/ndindex.rs

@@ -132,10 +132,10 @@ macro_rules! ndindex_with_array {
             }
 
             #[inline]
-            fn index_unchecked(&self, strides: &$ix_n) -> isize {
+            fn index_unchecked(&self, _strides: &$ix_n) -> isize {
                 $(
-                stride_offset(self[$index], get!(strides, $index)) + 
-                )+
+                stride_offset(self[$index], get!(_strides, $index)) + 
+                )*
                 0
             }
         }
@@ -157,7 +157,7 @@ macro_rules! ndindex_with_array {
                               self, strides.ndim());
                 $(
                 stride_offset(get!(self, $index), get!(strides, $index)) + 
-                )+
+                )*
                 0
             }
         }
@@ -179,7 +179,7 @@ macro_rules! ndindex_with_array {
                               self, strides.ndim());
                 $(
                 stride_offset(self[$index], get!(strides, $index)) + 
-                )+
+                )*
                 0
             }
         }
@@ -188,6 +188,7 @@ macro_rules! ndindex_with_array {
 }
 
 ndindex_with_array!{
+    [0, Ix0]
     [1, Ix1 0]
     [2, Ix2 0 1]
     [3, Ix3 0 1 2]

tests/ixdyn.rs

@@ -3,6 +3,7 @@ extern crate ndarray;
 
 use ndarray::Array;
 use ndarray::Ix3;
+use ndarray::IntoDimension;
 use ndarray::ShapeBuilder;
 
 #[test]
@@ -98,3 +99,50 @@ fn test_ixdyn_uget() {
     }
     assert_eq!(sum, 10.);
 }
+
+#[test]
+fn test_0() {
+    let mut a = Array::zeros(vec![]);
+    let z = vec![].into_dimension();
+    assert_eq!(a[z.clone()], 0.);
+    a[[]] = 1.;
+    assert_eq!(a[[]], 1.);
+    assert_eq!(a.len(), 1);
+    assert_eq!(a.as_slice().unwrap(), &[1.]);
+
+    let mut a = Array::zeros(vec![].f());
+    assert_eq!(a[[]], 0.);
+    a[[]] = 1.;
+    assert_eq!(a[[]], 1.);
+    assert_eq!(a.len(), 1);
+    assert_eq!(a.as_slice().unwrap(), &[1.]);
+}
+
+#[test]
+fn test_0_add() {
+    let mut a = Array::zeros(vec![]);
+    a += 1.;
+    assert_eq!(a[[]], 1.);
+    a += 2.;
+    assert_eq!(a[[]], 3.);
+}
+
+#[test]
+fn test_0_add_add() {
+    let mut a = Array::zeros(vec![]);
+    a += 1.;
+    let mut b = Array::zeros(vec![]);
+    b += 1.;
+    a += &b;
+    assert_eq!(a[[]], 2.);
+}
+
+#[test]
+fn test_0_add_broad() {
+    let mut b = Array::from_vec(vec![5., 6.]);
+    let mut a = Array::zeros(vec![]);
+    a += 1.;
+    b += &a;
+    assert_eq!(b[0], 6.);
+    assert_eq!(b[1], 7.);
+}