numpy · charris · Jul 30, 2014 · Jul 29, 2014 · Jul 29, 2014
diff --git a/doc/release/1.9.0-notes.rst b/doc/release/1.9.0-notes.rst
@@ -6,8 +6,6 @@ This release supports Python 2.6 - 2.7 and 3.2 - 3.4.
 
 Highlights
 ==========
-* Addition of `__numpy_ufunc__` to allow overriding ufuncs in ndarray
-  subclasses.
 * Numerous performance improvements in various areas, most notably indexing and
   operations on small arrays are significantly faster.
   Indexing operations now also release the GIL.
@@ -269,13 +267,6 @@ ufunc reductions do since 1.7. One can now say axis=(index, index) to pick a
 list of axes for the reduction. The ``keepdims`` keyword argument was also
 added to allow convenient broadcasting to arrays of the original shape.
 
-Ufunc and Dot Overrides
-~~~~~~~~~~~~~~~~~~~~~~~
-For better compatibility with external objects you can now override
-universal functions (ufuncs), ``numpy.core._dotblas.dot``, and
-``numpy.core.multiarray.dot`` (the numpy.dot functions). By defining a
-``__numpy_ufunc__`` method.
-
 Dtype parameter added to ``np.linspace`` and ``np.logspace``
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 The returned data type from the ``linspace`` and ``logspace`` functions can

diff --git a/doc/source/reference/arrays.classes.rst b/doc/source/reference/arrays.classes.rst
@@ -39,76 +39,6 @@ Special attributes and methods
 
 Numpy provides several hooks that classes can customize:
 
-.. function:: class.__numpy_ufunc__(self, ufunc, method, i, inputs, **kwargs)
-
-   .. versionadded:: 1.9
-
-   Any class (ndarray subclass or not) can define this method to
-   override behavior of Numpy's ufuncs. This works quite similarly to
-   Python's ``__mul__`` and other binary operation routines.
-
-   - *ufunc* is the ufunc object that was called. 
-   - *method* is a string indicating which Ufunc method was called
-     (one of ``"__call__"``, ``"reduce"``, ``"reduceat"``,
-     ``"accumulate"``, ``"outer"``, ``"inner"``). 
-   - *i* is the index of *self* in *inputs*.
-   - *inputs* is a tuple of the input arguments to the ``ufunc``
-   - *kwargs* is a dictionary containing the optional input arguments
-     of the ufunc. The ``out`` argument is always contained in
-     *kwargs*, if given. See the discussion in :ref:`ufuncs` for
-     details.
-
-   The method should return either the result of the operation, or
-   :obj:`NotImplemented` if the operation requested is not
-   implemented.
-
-   If one of the arguments has a :func:`__numpy_ufunc__` method, it is
-   executed *instead* of the ufunc.  If more than one of the input
-   arguments implements :func:`__numpy_ufunc__`, they are tried in the
-   order: subclasses before superclasses, otherwise left to right. The
-   first routine returning something else than :obj:`NotImplemented`
-   determines the result. If all of the :func:`__numpy_ufunc__`
-   operations return :obj:`NotImplemented`, a :exc:`TypeError` is
-   raised.
-
-   If an :class:`ndarray` subclass defines the :func:`__numpy_ufunc__`
-   method, this disables the :func:`__array_wrap__`,
-   :func:`__array_prepare__`, :data:`__array_priority__` mechanism
-   described below.
-
-   .. note:: In addition to ufuncs, :func:`__numpy_ufunc__` also
-      overrides the behavior of :func:`numpy.dot` even though it is
-      not an Ufunc.
-
-   .. note:: If you also define right-hand binary operator override
-      methods (such as ``__rmul__``) or comparison operations (such as
-      ``__gt__``) in your class, they take precedence over the
-      :func:`__numpy_ufunc__` mechanism when resolving results of
-      binary operations (such as ``ndarray_obj * your_obj``).
-
-      The technical special case is: ``ndarray.__mul__`` returns
-      ``NotImplemented`` if the other object is *not* a subclass of
-      :class:`ndarray`, and defines both ``__numpy_ufunc__`` and
-      ``__rmul__``. Similar exception applies for the other operations
-      than multiplication.
-
-      In such a case, when computing a binary operation such as
-      ``ndarray_obj * your_obj``, your ``__numpy_ufunc__`` method
-      *will not* be called.  Instead, the execution passes on to your
-      right-hand ``__rmul__`` operation, as per standard Python
-      operator override rules.
-
-      Similar special case applies to *in-place operations*: If you
-      define ``__rmul__``, then ``ndarray_obj *= your_obj`` *will not*
-      call your ``__numpy_ufunc__`` implementation. Instead, the
-      default Python behavior ``ndarray_obj = ndarray_obj * your_obj``
-      occurs.
-
-      Note that the above discussion applies only to Python's builtin
-      binary operation mechanism. ``np.multiply(ndarray_obj,
-      your_obj)`` always calls only your ``__numpy_ufunc__``, as
-      expected.
-
 .. function:: class.__array_finalize__(self)
 
    This method is called whenever the system internally allocates a

diff --git a/numpy/core/src/private/ufunc_override.h b/numpy/core/src/private/ufunc_override.h
@@ -188,6 +188,10 @@ PyUFunc_CheckOverride(PyUFuncObject *ufunc, char *method,
     /* Pos of each override in args */
     int with_override_pos[NPY_MAXARGS];
 
+    /* disabled until remaining issues are fixed */
+    *result = NULL;
+    return 0;
+
     /*
      * Check inputs
      */

diff --git a/numpy/core/tests/test_blasdot.py b/numpy/core/tests/test_blasdot.py
@@ -152,6 +152,7 @@ def test_dot_array_order():
                     assert_almost_equal(b.dot(c), _dot(b, c), decimal=prec)
                     assert_almost_equal(c.T.dot(b.T), _dot(c.T, b.T), decimal=prec)
 
+@dec.skipif(True) # ufunc override disabled for 1.9
 def test_dot_override():
     class A(object):
         def __numpy_ufunc__(self, ufunc, method, pos, inputs, **kwargs):

diff --git a/numpy/core/tests/test_multiarray.py b/numpy/core/tests/test_multiarray.py
@@ -1640,6 +1640,7 @@ def test_dot(self):
         a.dot(b=b, out=c)
         assert_equal(c, np.dot(a, b))
 
+    @dec.skipif(True) # ufunc override disabled for 1.9
     def test_dot_override(self):
         class A(object):
             def __numpy_ufunc__(self, ufunc, method, pos, inputs, **kwargs):
@@ -1770,6 +1771,7 @@ def test_conjugate(self):
 
 
 class TestBinop(object):
+    @dec.skipif(True) # ufunc override disabled for 1.9
     def test_ufunc_override_rop_precedence(self):
         # Check that __rmul__ and other right-hand operations have
         # precedence over __numpy_ufunc__
@@ -1888,6 +1890,7 @@ def __rop__(self, *other):
             yield check, op_name, True
             yield check, op_name, False
 
+    @dec.skipif(True) # ufunc override disabled for 1.9
     def test_ufunc_override_rop_simple(self):
         # Check parts of the binary op overriding behavior in an
         # explicit test case that is easier to understand.

diff --git a/numpy/core/tests/test_umath.py b/numpy/core/tests/test_umath.py
@@ -962,6 +962,7 @@ def __array__(self):
         assert_equal(ncu.maximum(a, B()), 0)
         assert_equal(ncu.maximum(a, C()), 0)
 
+    @dec.skipif(True) # ufunc override disabled for 1.9
     def test_ufunc_override(self):
         class A(object):
             def __numpy_ufunc__(self, func, method, pos, inputs, **kwargs):
@@ -988,6 +989,7 @@ def __numpy_ufunc__(self, func, method, pos, inputs, **kwargs):
         assert_equal(res0[5], {})
         assert_equal(res1[5], {})
 
+    @dec.skipif(True) # ufunc override disabled for 1.9
     def test_ufunc_override_mro(self):
 
         # Some multi arg functions for testing.
@@ -1081,6 +1083,7 @@ def __numpy_ufunc__(self, func, method, pos, inputs, **kwargs):
         assert_raises(TypeError, four_mul_ufunc, 1, 2, c_sub, c)
         assert_raises(TypeError, four_mul_ufunc, 1, c, c_sub, c)
 
+    @dec.skipif(True) # ufunc override disabled for 1.9
     def test_ufunc_override_methods(self):
         class A(object):
             def __numpy_ufunc__(self, ufunc, method, pos, inputs, **kwargs):
@@ -1184,6 +1187,7 @@ def __numpy_ufunc__(self, ufunc, method, pos, inputs, **kwargs):
         assert_equal(res[3], 0)
         assert_equal(res[4], (a, [4, 2], 'b0'))
 
+    @dec.skipif(True) # ufunc override disabled for 1.9
     def test_ufunc_override_out(self):
         class A(object):
             def __numpy_ufunc__(self, ufunc, method, pos, inputs, **kwargs):
@@ -1218,6 +1222,7 @@ def __numpy_ufunc__(self, ufunc, method, pos, inputs, **kwargs):
         assert_equal(res7['out'][0], 'out0')
         assert_equal(res7['out'][1], 'out1')
 
+    @dec.skipif(True) # ufunc override disabled for 1.9
     def test_ufunc_override_exception(self):
         class A(object):
             def __numpy_ufunc__(self, *a, **kwargs):

diff --git a/numpy/lib/tests/test_twodim_base.py b/numpy/lib/tests/test_twodim_base.py
@@ -324,6 +324,28 @@ def test_tril_triu_with_inf():
     assert_array_equal(np.tril(arr), out_tril)
 
 
+def test_tril_triu_dtype():
+    # Issue 4916
+    # tril and triu should return the same dtype as input
+    for c in np.typecodes['All']:
+        if c == 'V':
+            continue
+        arr = np.zeros((3, 3), dtype=c)
+        assert_equal(np.triu(arr).dtype, arr.dtype)
+        assert_equal(np.tril(arr).dtype, arr.dtype)
+
+    # check special cases
+    arr = np.array([['2001-01-01T12:00', '2002-02-03T13:56'],
+                    ['2004-01-01T12:00', '2003-01-03T13:45']],
+                   dtype='datetime64')
+    assert_equal(np.triu(arr).dtype, arr.dtype)
+    assert_equal(np.tril(arr).dtype, arr.dtype)
+
+    arr = np.zeros((3,3), dtype='f4,f4')
+    assert_equal(np.triu(arr).dtype, arr.dtype)
+    assert_equal(np.tril(arr).dtype, arr.dtype)
+
+
 def test_mask_indices():
     # simple test without offset
     iu = mask_indices(3, np.triu)

diff --git a/numpy/lib/twodim_base.py b/numpy/lib/twodim_base.py
@@ -453,7 +453,7 @@ def tril(m, k=0):
     m = asanyarray(m)
     mask = tri(*m.shape[-2:], k=k, dtype=bool)
 
-    return where(mask, m, 0)
+    return where(mask, m, zeros(1, m.dtype))
 
 
 def triu(m, k=0):
@@ -481,7 +481,7 @@ def triu(m, k=0):
     m = asanyarray(m)
     mask = tri(*m.shape[-2:], k=k-1, dtype=bool)
 
-    return where(mask, 0, m)
+    return where(mask, zeros(1, m.dtype), m)
 
 
 # Originally borrowed from John Hunter and matplotlib