diff options
| -rw-r--r-- | doc/release/upcoming_changes/14981.compatibility.rst | 10 | ||||
| -rw-r--r-- | numpy/core/tests/test_regression.py | 8 | ||||
| -rw-r--r-- | numpy/lib/arraysetops.py | 26 | ||||
| -rw-r--r-- | numpy/lib/tests/test_arraysetops.py | 19 |
4 files changed, 41 insertions, 22 deletions
diff --git a/doc/release/upcoming_changes/14981.compatibility.rst b/doc/release/upcoming_changes/14981.compatibility.rst new file mode 100644 index 000000000..90cf866f2 --- /dev/null +++ b/doc/release/upcoming_changes/14981.compatibility.rst @@ -0,0 +1,10 @@ +`np.ediff1d` casting behaviour with ``to_end`` and ``to_begin`` +--------------------------------------------------------------- + +`np.ediff1d` now uses the ``"same_kind"`` casting rule for +its additional ``to_end`` and ``to_begin`` arguments. This +ensures type safety except when the input array has a smaller +integer type than ``to_begin`` or ``to_end``. +In rare cases, the behaviour will be more strict than it was +previously in 1.16 and 1.17. This is necessary to solve issues +with floating point NaN. diff --git a/numpy/core/tests/test_regression.py b/numpy/core/tests/test_regression.py index d5de0f2b2..b215163ae 100644 --- a/numpy/core/tests/test_regression.py +++ b/numpy/core/tests/test_regression.py @@ -2467,8 +2467,11 @@ class TestRegression(object): x = np.array([1, 2, 4, 7, 0], dtype=np.int16) res = np.ediff1d(x, to_begin=-99, to_end=np.array([88, 99])) assert_equal(res, [-99, 1, 2, 3, -7, 88, 99]) - assert_raises(ValueError, np.ediff1d, x, to_begin=(1<<20)) - assert_raises(ValueError, np.ediff1d, x, to_end=(1<<20)) + + # The use of safe casting means, that 1<<20 is cast unsafely, an + # error may be better, but currently there is no mechanism for it. + res = np.ediff1d(x, to_begin=(1<<20), to_end=(1<<20)) + assert_equal(res, [0, 1, 2, 3, -7, 0]) def test_pickle_datetime64_array(self): # gh-12745 (would fail with pickle5 installed) @@ -2513,3 +2516,4 @@ class TestRegression(object): assert arr.size * arr.itemsize > 2 ** 31 c_arr = np.ctypeslib.as_ctypes(arr) assert_equal(c_arr._length_, arr.size) + diff --git a/numpy/lib/arraysetops.py b/numpy/lib/arraysetops.py index 2309f7e42..d65316598 100644 --- a/numpy/lib/arraysetops.py +++ b/numpy/lib/arraysetops.py @@ -94,8 +94,7 @@ def ediff1d(ary, to_end=None, to_begin=None): # force a 1d array ary = np.asanyarray(ary).ravel() - # enforce propagation of the dtype of input - # ary to returned result + # enforce that the dtype of `ary` is used for the output dtype_req = ary.dtype # fast track default case @@ -105,22 +104,23 @@ def ediff1d(ary, to_end=None, to_begin=None): if to_begin is None: l_begin = 0 else: - _to_begin = np.asanyarray(to_begin, dtype=dtype_req) - if not np.all(_to_begin == to_begin): - raise ValueError("cannot convert 'to_begin' to array with dtype " - "'%r' as required for input ary" % dtype_req) - to_begin = _to_begin.ravel() + to_begin = np.asanyarray(to_begin) + if not np.can_cast(to_begin, dtype_req, casting="same_kind"): + raise TypeError("dtype of `to_end` must be compatible " + "with input `ary` under the `same_kind` rule.") + + to_begin = to_begin.ravel() l_begin = len(to_begin) if to_end is None: l_end = 0 else: - _to_end = np.asanyarray(to_end, dtype=dtype_req) - # check that casting has not overflowed - if not np.all(_to_end == to_end): - raise ValueError("cannot convert 'to_end' to array with dtype " - "'%r' as required for input ary" % dtype_req) - to_end = _to_end.ravel() + to_end = np.asanyarray(to_end) + if not np.can_cast(to_end, dtype_req, casting="same_kind"): + raise TypeError("dtype of `to_end` must be compatible " + "with input `ary` under the `same_kind` rule.") + + to_end = to_end.ravel() l_end = len(to_end) # do the calculation in place and copy to_begin and to_end diff --git a/numpy/lib/tests/test_arraysetops.py b/numpy/lib/tests/test_arraysetops.py index fd21a7f76..1d38d8d27 100644 --- a/numpy/lib/tests/test_arraysetops.py +++ b/numpy/lib/tests/test_arraysetops.py @@ -135,9 +135,9 @@ class TestSetOps(object): None, np.nan), # should fail because attempting - # to downcast to smaller int type: - (np.array([1, 2, 3], dtype=np.int16), - np.array([5, 1<<20, 2], dtype=np.int32), + # to downcast to int type: + (np.array([1, 2, 3], dtype=np.int64), + np.array([5, 7, 2], dtype=np.float32), None), # should fail because attempting to cast # two special floating point values @@ -152,8 +152,8 @@ class TestSetOps(object): # specifically, raise an appropriate # Exception when attempting to append or # prepend with an incompatible type - msg = 'cannot convert' - with assert_raises_regex(ValueError, msg): + msg = 'must be compatible' + with assert_raises_regex(TypeError, msg): ediff1d(ary=ary, to_end=append, to_begin=prepend) @@ -163,9 +163,13 @@ class TestSetOps(object): "append," "expected", [ (np.array([1, 2, 3], dtype=np.int16), - 0, + 2**16, # will be cast to int16 under same kind rule. + 2**16 + 4, + np.array([0, 1, 1, 4], dtype=np.int16)), + (np.array([1, 2, 3], dtype=np.float32), + np.array([5], dtype=np.float64), None, - np.array([0, 1, 1], dtype=np.int16)), + np.array([5, 1, 1], dtype=np.float32)), (np.array([1, 2, 3], dtype=np.int32), 0, 0, @@ -187,6 +191,7 @@ class TestSetOps(object): to_end=append, to_begin=prepend) assert_equal(actual, expected) + assert actual.dtype == expected.dtype def test_isin(self): |