implement dpnp.signbit and dpnp.proj (#1535)

* implement dpnp.signbit and dpnp.proj

* address comments

* add sycl_q and usm_type tests for dpnp.proj

Author: vtavana

doc/reference/math.rst

@@ -169,6 +169,7 @@ Handling complex numbers
    dpnp.imag
    dpnp.conj
    dpnp.conjugate
+   dpnp.proj
 
 
 Extrema Finding

doc/reference/ufunc.rst

@@ -42,6 +42,7 @@ Math operations
    dpnp.log10
    dpnp.expm1
    dpnp.log1p
+   dpnp.proj
    dpnp.sqrt
    dpnp.square
    dpnp.reciprocal

dpnp/dpnp_algo/dpnp_elementwise_common.py

@@ -66,10 +66,14 @@
     "dpnp_logical_or",
     "dpnp_logical_xor",
     "dpnp_multiply",
+    "dpnp_negative",
     "dpnp_not_equal",
+    "dpnp_proj",
     "dpnp_remainder",
     "dpnp_right_shift",
     "dpnp_round",
+    "dpnp_sign",
+    "dpnp_signbit",
     "dpnp_sin",
     "dpnp_sqrt",
     "dpnp_square",
@@ -1456,6 +1460,43 @@ def dpnp_not_equal(x1, x2, out=None, order="K"):
     return dpnp_array._create_from_usm_ndarray(res_usm)
 
 
+_proj_docstring = """
+proj(x, out=None, order="K")
+
+Computes projection of each element `x_i` for input array `x`.
+
+Args:
+    x (dpnp.ndarray):
+        Input array, expected to have numeric data type.
+    out ({None, dpnp.ndarray}, optional):
+        Output array to populate.
+        Array have the correct shape and the expected data type.
+    order ("C","F","A","K", optional):
+        Memory layout of the newly output array, if parameter `out` is `None`.
+        Default: "K".
+Returns:
+    dpnp.ndarray:
+        An array containing the element-wise projection.
+        The returned array has the same data type as `x`.
+"""
+
+
+proj_func = UnaryElementwiseFunc(
+    "proj", ti._proj_result_type, ti._proj, _proj_docstring
+)
+
+
+def dpnp_proj(x, out=None, order="K"):
+    """Invokes proj() from dpctl.tensor implementation for proj() function."""
+
+    # dpctl.tensor only works with usm_ndarray
+    x1_usm = dpnp.get_usm_ndarray(x)
+    out_usm = None if out is None else dpnp.get_usm_ndarray(out)
+
+    res_usm = proj_func(x1_usm, out=out_usm, order=order)
+    return dpnp_array._create_from_usm_ndarray(res_usm)
+
+
 _remainder_docstring_ = """
 remainder(x1, x2, out=None, order='K')
 Calculates the remainder of division for each element `x1_i` of the input array
@@ -1642,6 +1683,44 @@ def dpnp_sign(x, out=None, order="K"):
     return dpnp_array._create_from_usm_ndarray(res_usm)
 
 
+_signbit_docstring = """
+signbit(x, out=None, order="K")
+
+Computes an indication of whether the sign bit of each element `x_i` of
+input array `x` is set.
+
+Args:
+    x (dpnp.ndarray):
+        Input array, expected to have numeric data type.
+    out ({None, dpnp.ndarray}, optional):
+        Output array to populate.
+        Array have the correct shape and the expected data type.
+    order ("C","F","A","K", optional):
+        Memory layout of the newly output array, if parameter `out` is `None`.
+        Default: "K".
+Returns:
+    dpnp.ndarray:
+        An array containing the element-wise results. The returned array
+        must have a data type of `bool`.
+"""
+
+
+signbit_func = UnaryElementwiseFunc(
+    "signbit", ti._signbit_result_type, ti._signbit, _signbit_docstring
+)
+
+
+def dpnp_signbit(x, out=None, order="K"):
+    """Invokes signbit() from dpctl.tensor implementation for signbit() function."""
+
+    # dpctl.tensor only works with usm_ndarray
+    x1_usm = dpnp.get_usm_ndarray(x)
+    out_usm = None if out is None else dpnp.get_usm_ndarray(out)
+
+    res_usm = signbit_func(x1_usm, out=out_usm, order=order)
+    return dpnp_array._create_from_usm_ndarray(res_usm)
+
+
 _sin_docstring = """
 sin(x, out=None, order='K')
 Computes sine for each element `x_i` of input array `x`.

dpnp/dpnp_iface_mathematical.py

@@ -58,9 +58,11 @@
     dpnp_floor_divide,
     dpnp_multiply,
     dpnp_negative,
+    dpnp_proj,
     dpnp_remainder,
     dpnp_round,
     dpnp_sign,
+    dpnp_signbit,
     dpnp_subtract,
     dpnp_trunc,
 )
@@ -101,10 +103,12 @@
     "negative",
     "power",
     "prod",
+    "proj",
     "remainder",
     "rint",
     "round",
     "sign",
+    "signbit",
     "subtract",
     "sum",
     "trapz",
@@ -1562,6 +1566,65 @@ def negative(
     )
 
 
+def proj(
+    x,
+    /,
+    out=None,
+    *,
+    order="K",
+    where=True,
+    dtype=None,
+    subok=True,
+    **kwargs,
+):
+    """
+    Returns the projection of a number onto the Riemann sphere.
+
+    For all infinite complex numbers (including the cases where one component is infinite and the other is `NaN`),
+    the function returns `(inf, 0.0)` or `(inf, -0.0)`.
+    For finite complex numbers, the input is returned.
+    All real-valued numbers are treated as complex numbers with positive zero imaginary part.
+
+    Returns
+    -------
+    out : dpnp.ndarray
+        The projection of each element of `x`.
+
+    Limitations
+    -----------
+    Parameters `x` is only supported as either :class:`dpnp.ndarray` or :class:`dpctl.tensor.usm_ndarray`.
+    Parameters `where`, `dtype` and `subok` are supported with their default values.
+    Keyword arguments `kwargs` are currently unsupported.
+    Input array data types are limited by supported DPNP :ref:`Data types`.
+
+    See Also
+    --------
+    :obj:`dpnp.abs` : Returns the magnitude of a complex number, element-wise.
+    :obj:`dpnp.conj` : Return the complex conjugate, element-wise.
+
+    Examples
+    --------
+    >>> import dpnp as np
+    >>> np.proj(np.array([1, -2.3, 2.1-1.7j]))
+    array([ 1. +0.j, -2.3+0.j,  2.1-1.7.j])
+
+    >>> np.proj(np.array([complex(1,np.inf), complex(1,-np.inf), complex(np.inf,-1),]))
+    array([inf+0.j, inf-0.j, inf-0.j])
+    """
+
+    return check_nd_call_func(
+        None,
+        dpnp_proj,
+        x,
+        out=out,
+        where=where,
+        order=order,
+        dtype=dtype,
+        subok=subok,
+        **kwargs,
+    )
+
+
 def power(x1, x2, /, out=None, *, where=True, dtype=None, subok=True, **kwargs):
     """
     First array elements raised to powers from second array, element-wise.
@@ -1931,6 +1994,10 @@ def sign(
     Input array data types are limited by supported DPNP :ref:`Data types`.
     However, if the input array data type is complex, the function will be executed sequentially on CPU.
 
+    See Also
+    --------
+    :obj:`dpnp.signbit` : Returns element-wise `True` where signbit is set (less than zero).
+
     Examples
     --------
     >>> import dpnp as np
@@ -1968,6 +2035,63 @@ def sign(
         )
 
 
+def signbit(
+    x,
+    /,
+    out=None,
+    *,
+    order="K",
+    where=True,
+    dtype=None,
+    subok=True,
+    **kwargs,
+):
+    """
+    Returns element-wise `True` where signbit is set (less than zero).
+
+    For full documentation refer to :obj:`numpy.signbit`.
+
+    Returns
+    -------
+    out : dpnp.ndarray
+        A boolean array with indication of the sign of each element of `x`.
+
+    Limitations
+    -----------
+    Parameters `x` is only supported as either :class:`dpnp.ndarray` or :class:`dpctl.tensor.usm_ndarray`.
+    Parameters `where`, `dtype` and `subok` are supported with their default values.
+    Keyword argument `kwargs` is currently unsupported.
+    Otherwise the function will be executed sequentially on CPU.
+    Input array data types are limited by supported real-valued data types.
+
+    See Also
+    --------
+    :obj:`dpnp.sign` : Returns an element-wise indication of the sign of a number.
+
+    Examples
+    --------
+    >>> import dpnp as np
+    >>> np.signbit(np.array([-1.2]))
+    array([True])
+
+    >>> np.signbit(np.array([1, -2.3, 2.1]))
+    array([False,  True, False])
+
+    """
+
+    return check_nd_call_func(
+        numpy.signbit,
+        dpnp_signbit,
+        x,
+        out=out,
+        where=where,
+        order=order,
+        dtype=dtype,
+        subok=subok,
+        **kwargs,
+    )
+
+
 def subtract(
     x1,
     x2,

tests/skipped_tests.tbl

@@ -111,8 +111,6 @@ tests/test_umath.py::test_umaths[('positive', 'i')]
 tests/test_umath.py::test_umaths[('positive', 'l')]
 tests/test_umath.py::test_umaths[('positive', 'f')]
 tests/test_umath.py::test_umaths[('positive', 'd')]
-tests/test_umath.py::test_umaths[('signbit', 'f')]
-tests/test_umath.py::test_umaths[('signbit', 'd')]
 tests/test_umath.py::test_umaths[('spacing', 'f')]
 tests/test_umath.py::test_umaths[('spacing', 'd')]
 
@@ -517,7 +515,6 @@ tests/third_party/cupy/math_tests/test_floating.py::TestFloating::test_frexp
 tests/third_party/cupy/math_tests/test_floating.py::TestFloating::test_ldexp
 tests/third_party/cupy/math_tests/test_floating.py::TestFloating::test_nextafter_combination
 tests/third_party/cupy/math_tests/test_floating.py::TestFloating::test_nextafter_float
-tests/third_party/cupy/math_tests/test_floating.py::TestFloating::test_signbit
 
 tests/third_party/cupy/math_tests/test_misc.py::TestMisc::test_clip_min_max_none
 tests/third_party/cupy/math_tests/test_misc.py::TestMisc::test_external_clip4

tests/skipped_tests_gpu.tbl

@@ -63,8 +63,6 @@ tests/test_umath.py::test_umaths[('positive', 'i')]
 tests/test_umath.py::test_umaths[('positive', 'l')]
 tests/test_umath.py::test_umaths[('positive', 'f')]
 tests/test_umath.py::test_umaths[('positive', 'd')]
-tests/test_umath.py::test_umaths[('signbit', 'f')]
-tests/test_umath.py::test_umaths[('signbit', 'd')]
 tests/test_umath.py::test_umaths[('spacing', 'f')]
 tests/test_umath.py::test_umaths[('spacing', 'd')]
 
@@ -659,7 +657,6 @@ tests/third_party/cupy/math_tests/test_floating.py::TestFloating::test_frexp
 tests/third_party/cupy/math_tests/test_floating.py::TestFloating::test_ldexp
 tests/third_party/cupy/math_tests/test_floating.py::TestFloating::test_nextafter_combination
 tests/third_party/cupy/math_tests/test_floating.py::TestFloating::test_nextafter_float
-tests/third_party/cupy/math_tests/test_floating.py::TestFloating::test_signbit
 
 tests/third_party/cupy/math_tests/test_misc.py::TestMisc::test_clip_min_max_none
 tests/third_party/cupy/math_tests/test_misc.py::TestMisc::test_external_clip4

tests/test_mathematical.py

@@ -14,6 +14,7 @@
 
 from .helper import (
     get_all_dtypes,
+    get_complex_dtypes,
     get_float_complex_dtypes,
     get_float_dtypes,
     has_support_aspect64,
@@ -442,6 +443,48 @@ def test_sign_boolean():
         dpnp.sign(dpnp_a)
 
 
+@pytest.mark.parametrize(
+    "data",
+    [[2, 0, -2], [1.1, -1.1]],
+    ids=["[2, 0, -2]", "[1.1, -1.1]"],
+)
+@pytest.mark.parametrize("dtype", get_all_dtypes(no_complex=True))
+def test_signbit(data, dtype):
+    np_a = numpy.array(data, dtype=dtype)
+    dpnp_a = dpnp.array(data, dtype=dtype)
+
+    result = dpnp.signbit(dpnp_a)
+    expected = numpy.signbit(np_a)
+    assert_allclose(result, expected)
+
+
+@pytest.mark.parametrize("dtype", get_complex_dtypes())
+def test_projection_infinity(dtype):
+    X = [
+        complex(1, 2),
+        complex(dpnp.inf, -1),
+        complex(0, -dpnp.inf),
+        complex(-dpnp.inf, dpnp.nan),
+    ]
+    Y = [
+        complex(1, 2),
+        complex(dpnp.inf, -0.0),
+        complex(dpnp.inf, -0.0),
+        complex(dpnp.inf, 0.0),
+    ]
+
+    result = dpnp.proj(dpnp.array(X, dtype=dtype))
+    expected = dpnp.array(Y, dtype=dtype)
+    assert_allclose(result, expected)
+
+
+@pytest.mark.parametrize("dtype", get_all_dtypes())
+def test_projection(dtype):
+    result = dpnp.proj(dpnp.array(1, dtype=dtype))
+    expected = dpnp.array(complex(1, 0))
+    assert_allclose(result, expected)
+
+
 @pytest.mark.parametrize("val_type", get_all_dtypes(no_none=True))
 @pytest.mark.parametrize("data_type", get_all_dtypes())
 @pytest.mark.parametrize("val", [1.5, 1, 5], ids=["1.5", "1", "5"])