Revamped np.reshape

Nucs · Nucs · commit de0b9e81bfa8 · 2019-07-26T17:27:39.000+03:00
diff --git a/src/NumSharp.Core/Creation/NdArray.ReShape.cs b/src/NumSharp.Core/Creation/NdArray.ReShape.cs
@@ -10,29 +10,46 @@ namespace NumSharp
     public partial class NDArray
     {
         /// <summary>
-        /// 
+        ///     Gives a new shape to an array without changing its data.
         /// </summary>
-        /// <param name="shape"></param>
-        /// <param name="order">
-        /// C: row major
-        /// F: column major
-        /// </param>
-        /// <returns></returns>
-        public NDArray reshape(Shape shape, char order = 'C')
+        /// <param name="newshape">The new shape should be compatible with the original shape. If an integer, then the result will be a 1-D array of that length. One shape dimension can be -1. In this case, the value is inferred from the length of the array and remaining dimensions.</param>
+        /// <returns>This will be a new view object if possible; otherwise, it will be a copy. Note there is no guarantee of the memory layout (C- or Fortran- contiguous) of the returned array.</returns>
+        /// <remarks>https://docs.scipy.org/doc/numpy/reference/generated/numpy.reshape.html</remarks>
+        public NDArray reshape(ref Shape newshape)
         {
-            //TODO! support for order 'F'
-            return new NDArray(new UnmanagedStorage(Storage.InternalArray, shape)) {TensorEngine = TensorEngine};
+            if (newshape.size == 0 && size != 0)
+                throw new ArgumentException("Value cannot be an empty collection.", nameof(newshape));
+
+            if (Shape.IsSliced)
+                Console.WriteLine("reshaping a sliced NDArray performs performs a copy.");
+
+            var storage = newshape.IsSliced ? new UnmanagedStorage(Storage.CloneData(), newshape) : Storage.Alias(newshape);
+            return new NDArray(storage) { TensorEngine = TensorEngine };
         }
 
-        public NDArray reshape(params int[] shape)
+        /// <summary>
+        ///     Gives a new shape to an array without changing its data.
+        /// </summary>
+        /// <param name="newshape">The new shape should be compatible with the original shape. If an integer, then the result will be a 1-D array of that length. One shape dimension can be -1. In this case, the value is inferred from the length of the array and remaining dimensions.</param>
+        /// <returns>This will be a new view object if possible; otherwise, it will be a copy. Note there is no guarantee of the memory layout (C- or Fortran- contiguous) of the returned array.</returns>
+        /// <remarks>https://docs.scipy.org/doc/numpy/reference/generated/numpy.reshape.html</remarks>
+        public NDArray reshape(Shape newshape)
         {
-            //TODO support negative index.
-            return new NDArray(new UnmanagedStorage(Storage.InternalArray, shape)) {TensorEngine = TensorEngine};
+            return reshape(ref newshape);
         }
 
-        public NDArray reshape(ref Shape shape)
+        /// <summary>
+        ///     Gives a new shape to an array without changing its data.
+        /// </summary>
+        /// <param name="shape">The new shape should be compatible with the original shape. If an integer, then the result will be a 1-D array of that length. One shape dimension can be -1. In this case, the value is inferred from the length of the array and remaining dimensions.</param>
+        /// <returns>This will be a new view object if possible; otherwise, it will be a copy. Note there is no guarantee of the memory layout (C- or Fortran- contiguous) of the returned array.</returns>
+        /// <remarks>https://docs.scipy.org/doc/numpy/reference/generated/numpy.reshape.html</remarks>
+        public NDArray reshape(params int[] shape)
         {
-            return new NDArray(new UnmanagedStorage(Storage.InternalArray, shape)) {TensorEngine = TensorEngine};
+            if (shape.Length == 0 && size != 0)
+                throw new ArgumentException("Value cannot be an empty collection.", nameof(shape));
+
+            return reshape(new Shape(shape));
         }
 
         protected static int FindNegativeIndex(params int[] shape)
diff --git a/src/NumSharp.Core/Manipulation/np.reshape.cs b/src/NumSharp.Core/Manipulation/np.reshape.cs
@@ -16,8 +16,8 @@ public static partial class np
         public static NDArray reshape(NDArray nd, params int[] shape)
         {
             return nd.reshape(shape);
-        }     
-        
+        }
+
         /// <summary>
         ///     Gives a new shape to an array without changing its data.
         /// </summary>
