Adds tests for angle

Author: ndgrigorian

dpctl/tensor/libtensor/include/kernels/elementwise_functions/angle.hpp

@@ -1,5 +1,4 @@
-//=== angle.hpp -   Unary function ANGLE                     ------
-//*-C++-*--/===//
+//=== angle.hpp -   Unary function ANGLE              ------*-C++-*--/===//
 //
 //                      Data Parallel Control (dpctl)
 //

dpctl/tests/elementwise/test_angle.py

@@ -0,0 +1,92 @@
+#                       Data Parallel Control (dpctl)
+#
+#  Copyright 2020-2023 Intel Corporation
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+import itertools
+
+import numpy as np
+import pytest
+
+import dpctl.tensor as dpt
+from dpctl.tensor._type_utils import _can_cast
+from dpctl.tests.helper import get_queue_or_skip, skip_if_dtype_not_supported
+
+from .utils import _all_dtypes, _complex_fp_dtypes, _no_complex_dtypes
+
+
+@pytest.mark.parametrize("dtype", _all_dtypes)
+def test_angle_out_type(dtype):
+    q = get_queue_or_skip()
+    skip_if_dtype_not_supported(dtype, q)
+
+    x = dpt.asarray(1, dtype=dtype, sycl_queue=q)
+    dt = dpt.dtype(dtype)
+    dev = q.sycl_device
+    _fp16 = dev.has_aspect_fp16
+    _fp64 = dev.has_aspect_fp64
+    if _can_cast(dt, dpt.complex64, _fp16, _fp64):
+        assert dpt.angle(x).dtype == dpt.float32
+    else:
+        assert dpt.angle(x).dtype == dpt.float64
+
+
+@pytest.mark.parametrize("dtype", _no_complex_dtypes[1:])
+def test_angle_real(dtype):
+    q = get_queue_or_skip()
+    skip_if_dtype_not_supported(dtype, q)
+
+    x = dpt.arange(10, dtype=dtype, sycl_queue=q)
+    r = dpt.angle(x)
+
+    assert dpt.all(r == 0)
+
+
+@pytest.mark.parametrize("dtype", _complex_fp_dtypes)
+def test_angle_complex(dtype):
+    q = get_queue_or_skip()
+    skip_if_dtype_not_supported(dtype, q)
+
+    tol = 8 * dpt.finfo(dtype).resolution
+    vals = dpt.pi * dpt.arange(10, dtype=dpt.finfo(dtype).dtype, sycl_queue=q)
+
+    x = dpt.zeros(10, dtype=dtype, sycl_queue=q)
+
+    x.imag[...] = vals
+    r = dpt.angle(x)
+    expected = dpt.atan2(x.imag, x.real)
+    assert dpt.allclose(r, expected, atol=tol, rtol=tol)
+
+    x.real[...] += dpt.pi
+    r = dpt.angle(x)
+    expected = dpt.atan2(x.imag, x.real)
+    assert dpt.allclose(r, expected, atol=tol, rtol=tol)
+
+
+@pytest.mark.parametrize("dtype", ["c8", "c16"])
+def test_angle_special_cases(dtype):
+    q = get_queue_or_skip()
+    skip_if_dtype_not_supported(dtype, q)
+
+    vals = [np.nan, -np.nan, np.inf, -np.inf, +0.0, -0.0]
+    vals = [complex(*val) for val in itertools.product(vals, repeat=2)]
+
+    x = dpt.asarray(vals, dtype=dtype, sycl_queue=q)
+
+    r = dpt.angle(x)
+    expected = dpt.atan2(x.imag, x.real)
+
+    tol = 8 * dpt.finfo(dtype).resolution
+
+    assert dpt.allclose(r, expected, atol=tol, rtol=tol, equal_nan=True)