numpy-like copy (#581)

* numpy-like copy

* Fix dtype initial

* fix impl bool+number

* small fix

* fix tests

Author: 1e-to

sdc/functions/numpy_like.py

@@ -48,6 +48,10 @@ def astype(self, dtype):
     pass
 
 
+def copy(self):
+    pass
+
+
 def isnan(self):
     pass
 
@@ -125,6 +129,39 @@ def sdc_astype_number_impl(self, dtype):
     ty_checker.raise_exc(self.dtype, 'str or type', 'self.dtype')
 
 
+@sdc_overload(copy)
+def sdc_copy_overload(self):
+    """
+    Intel Scalable Dataframe Compiler Developer Guide
+    *************************************************
+    Parallel replacement of numpy.copy.
+
+    .. only:: developer
+       Test: python -m sdc.runtests sdc.tests.test_sdc_numpy -k copy
+    """
+
+    if not isinstance(self, types.Array):
+        return None
+
+    dtype = self.dtype
+    if isinstance(dtype, (types.Number, types.Boolean, bool)):
+        def sdc_copy_number_impl(self):
+            length = len(self)
+            res = numpy.empty(length, dtype=dtype)
+            for i in prange(length):
+                res[i] = self[i]
+
+            return res
+
+        return sdc_copy_number_impl
+
+    if isinstance(dtype, types.npytypes.UnicodeCharSeq):
+        def sdc_copy_string_impl(self):
+            return self.copy()
+
+        return sdc_copy_string_impl
+
+
 @sdc_overload(notnan)
 def sdc_isnan_overload(self):
     """

sdc/tests/test_sdc_numpy.py

@@ -188,6 +188,57 @@ def sdc_impl(a):
             with self.subTest(data=case):
                 np.testing.assert_array_equal(sdc_func(a), ref_impl(a))
 
+    def test_copy(self):
+        def ref_impl(a):
+            return np.copy(a)
+
+        def sdc_impl(a):
+            return numpy_like.copy(a)
+
+        sdc_func = self.jit(sdc_impl)
+
+        cases = [[5, 2, 0, 333, -4], [3.3, 5.4, np.nan, 7.9, np.nan], [True, False, True], ['a', 'vv', 'o12oo']]
+        for case in cases:
+            a = np.array(case)
+            with self.subTest(data=case):
+                np.testing.assert_array_equal(sdc_func(a), ref_impl(a))
+
+    def test_copy_int(self):
+        def ref_impl():
+            a = np.array([5, 2, 0, 333, -4])
+            return np.copy(a)
+
+        def sdc_impl():
+            a = np.array([5, 2, 0, 333, -4])
+            return numpy_like.copy(a)
+
+        sdc_func = self.jit(sdc_impl)
+        np.testing.assert_array_equal(sdc_func(), ref_impl())
+
+    def test_copy_bool(self):
+        def ref_impl():
+            a = np.array([True, False, True])
+            return np.copy(a)
+
+        def sdc_impl():
+            a = np.array([True, False, True])
+            return numpy_like.copy(a)
+
+        sdc_func = self.jit(sdc_impl)
+        np.testing.assert_array_equal(sdc_func(), ref_impl())
+
+    @unittest.skip("Numba doesn't have string array")
+    def test_copy_str(self):
+        def ref_impl():
+            a = np.array(['a', 'vv', 'o12oo'])
+            return np.copy(a)
+
+        def sdc_impl():
+            a = np.array(['a', 'vv', 'o12oo'])
+            return numpy_like.copy(a)
+
+        sdc_func = self.jit(sdc_impl)
+        np.testing.assert_array_equal(sdc_func(), ref_impl())
 
 class TestArrayReductions(TestCase):
 

sdc/tests/tests_perf/test_perf_numpy.py

@@ -99,6 +99,11 @@ def _test_case(self, cases, name, total_data_length, data_num=1, input_data=test
         CE(type_='Numba', code='data.astype(np.int64)', jitted=True),
         CE(type_='SDC', code='sdc.functions.numpy_like.astype(data, np.int64)', jitted=True),
     ], usecase_params='data'),
+    TC(name='copy', size=[10 ** 7], call_expr=[
+        CE(type_='Python', code='np.copy(data)', jitted=False),
+        CE(type_='Numba', code='np.copy(data)', jitted=True),
+        CE(type_='SDC', code='sdc.functions.numpy_like.copy(data)', jitted=True),
+    ], usecase_params='data'),
     TC(name='isnan', size=[10 ** 7], call_expr=[
         CE(type_='Python', code='np.isnan(data)', jitted=False),
         CE(type_='Numba', code='np.isnan(data)', jitted=True),