Closes #3300: shape function (#3900)

Co-authored-by: Amanda Potts <[email protected]>

arkouda/numpy/__init__.py

@@ -96,4 +96,5 @@
 from arkouda.numpy.rec import *
 
 from ._numeric import *
+from ._utils import *
 from ._manipulation_functions import *

arkouda/numpy/_utils.py

@@ -0,0 +1,51 @@
+from typing import Iterable, Tuple, Union
+
+from numpy import ndarray
+
+from arkouda.numpy.dtypes import all_scalars, isSupportedDType
+from arkouda.pdarrayclass import pdarray
+from arkouda.strings import Strings
+
+__all__ = ["shape"]
+
+
+def shape(a: Union[pdarray, Strings, all_scalars]) -> Tuple:
+    """
+    Return the shape of an array.
+
+    Parameters
+    ----------
+    a : pdarray
+        Input array.
+
+    Returns
+    -------
+    shape : tuple of ints
+        The elements of the shape tuple give the lengths of the
+        corresponding array dimensions.
+
+    Examples
+    --------
+    >>> import arkouda as ak
+    >>> ak.shape(ak.eye(3,2))
+    (3, 2)
+    >>> ak.shape([[1, 3]])
+    (1, 2)
+    >>> ak.shape([0])
+    (1,)
+    >>> ak.shape(0)
+    ()
+
+    """
+    if isinstance(a, (pdarray, Strings, ndarray, Iterable)) and not isinstance(a, str):
+        try:
+            result = a.shape
+        except AttributeError:
+            from arkouda import array
+
+            result = array(a).shape
+        return result
+    elif isSupportedDType(a):
+        return ()
+    else:
+        raise TypeError("shape requires type pdarray, ndarray, Iterable, or numeric scalar.")

arkouda/numpy/dtypes/dtypes.py

@@ -57,6 +57,7 @@
     "intTypes",
     "int_scalars",
     "isSupportedBool",
+    "isSupportedDType",
     "isSupportedFloat",
     "isSupportedInt",
     "isSupportedNumber",
@@ -320,6 +321,10 @@ def isSupportedBool(num):
     return isinstance(num, ARKOUDA_SUPPORTED_BOOLS)
 
 
+def isSupportedDType(scalar):
+    return isinstance(scalar, ARKOUDA_SUPPORTED_DTYPES)
+
+
 def resolve_scalar_dtype(val: object) -> str:
     """
     Try to infer what dtype arkouda_server should treat val as.

tests/numpy/utils_test.py

@@ -0,0 +1,23 @@
+import pytest
+
+import arkouda as ak
+import numpy as np
+
+
+class TestFromNumericFunctions:
+
+    @pytest.mark.parametrize("x", [0, [0], [1, 2, 3], np.ndarray([0, 1, 2]), [[1, 3]], np.eye(3, 2)])
+    def test_shape(self, x):
+        assert ak.shape(x) == np.shape(x)
+
+    def test_shape_pdarray(self):
+        a = ak.arange(5)
+        assert ak.shape(a) == np.shape(a.to_ndarray())
+
+    def test_shape_strings(self):
+        a = ak.array(["a", "b", "c"])
+        assert ak.shape(a) == np.shape(a.to_ndarray())
+
+    @pytest.mark.skip_if_max_rank_less_than(2)
+    def test_shape_multidim_pdarray(self):
+        assert ak.shape(ak.eye(3, 2)) == (3, 2)