8000 BUG: Fix recarray getattr and getindex return types · numpy/numpy@3cd9e73 · GitHub
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BUG: Fix recarray getattr and getindex return types
This commit makes changes to `__getitem__` and `__getattr__` of recarrays: 1. recarrays no longer convert string ndarrays to chararrays, and instead simply return ndarrays of string type. 2. attribute access and index access of fields now behaves identically 3. dtype.type is now inherited when fields of structured type are accessed Demonstration: >>> rec = np.rec.array([('abc ', (1,1), 1), ('abc', (2,3), 1)], ... dtype=[('foo', 'S4'), ('bar', [('A', int), ('B', int)]), ('baz', int)]) Old Behavior: >>> type(rec.foo), type(rec['foo']) (numpy.core.defchararray.chararray, numpy.recarray) >>> type(rec.bar), type(rec['bar']), rec.bar.dtype.type (numpy.recarray, numpy.recarray, numpy.void) >>> type(rec.baz), type(rec['baz']) (numpy.ndarray, numpy.ndarray) New behavior: >>> type(rec.foo), type(rec['foo']) (numpy.ndarray, numpy.ndarray) >>> type(rec.bar), type(rec['bar']), rec.bar.dtype.type (numpy.recarray, numpy.recarray, numpy.record) >>> type(rec.baz), type(rec['baz']) (numpy.ndarray, numpy.ndarray)
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‎doc/release/1.10.0-notes.rst‎

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@@ -61,6 +61,15 @@ C API
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The changes to *swapaxes* also apply to the *PyArray_SwapAxes* C function,
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which now returns a view in all cases.
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recarray field return types
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~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Previously the returned types for recarray fields accessed by attribute and by
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index were inconsistent, and fields of string type were returned as chararrays.
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Now, fields accessed by either attribute or indexing will return an ndarray for
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fields of non-structured type, and a recarray for fields of structured type.
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Notably, this affect recarrays containing strings with whitespace, as trailing
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whitespace is trimmed from chararrays but kept in ndarrays of string type.
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Also, the dtype.type of nested structured fields is now inherited.
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New Features
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============

‎numpy/core/records.py‎

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@@ -40,7 +40,6 @@
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import os
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from . import numeric as sb
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from .defchararray import chararray
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from . import numerictypes as nt
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from numpy.compat import isfileobj, bytes, long
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@@ -238,17 +237,15 @@ def __getattribute__(self, attr):
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res = fielddict.get(attr, None)
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if res:
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obj = self.getfield(*res[:2])
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# if it has fields return a recarray,
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# if it's a string ('SU') return a chararray
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# if it has fields return a record,
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# otherwise return the object
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try:
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dt = obj.dtype
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except AttributeError:
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#happens if field is Object type
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return obj
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if dt.fields:
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return obj.view(obj.__class__)
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if dt.char in 'SU':
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return obj.view(chararray)
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return obj.view((record, obj.dtype.descr))
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return obj
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else:
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raise AttributeError("'record' object has no "
@@ -418,29 +415,37 @@ def __new__(subtype, shape, dtype=None, buf=None, offset=0, strides=None,
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return self
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def __getattribute__(self, attr):
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# See if ndarray has this attr, and return it if so. (note that this
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# means a field with the same name as an ndarray attr cannot be
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# accessed by attribute).
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try:
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return object.__getattribute__(self, attr)
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except AttributeError: # attr must be a fieldname
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pass
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# look for a field with this name
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fielddict = ndarray.__getattribute__(self, 'dtype').fields
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try:
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res = fielddict[attr][:2]
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except (TypeError, KeyError):
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raise AttributeError("record array has no attribute %s" % attr)
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raise AttributeError("recarray has no attribute %s" % attr)
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obj = self.getfield(*res)
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# if it has fields return a recarray, otherwise return
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# normal array
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if obj.dtype.fields:
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return obj
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if obj.dtype.char in 'SU':
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return obj.view(chararray)
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return obj.view(ndarray)
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# Save the dictionary
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# If the attr is a field name and not in the saved dictionary
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# Undo any "setting" of the attribute and do a setfield
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# Thus, you can't create attributes on-the-fly that are field names.
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# At this point obj will always be a recarray, since (see
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# PyArray_GetField) the type of obj is inherited. Next, if obj.dtype is
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# non-structured, convert it to an ndarray. If obj is structured leave
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# it as a recarray, but make sure to convert to the same dtype.type (eg
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# to preserve numpy.record type if present), since nested structured
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# fields do not inherit type.
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if obj.dtype.fields:
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return obj.view(dtype=(self.dtype.type, obj.dtype.descr))
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else:
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return obj.view(ndarray)
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# Save the dictionary.
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# If the attr is a field name and not in the saved dictionary
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# Undo any "setting" of the attribute and do a setfield
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# Thus, you can't create attributes on-the-fly that are field names.
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def __setattr__(self, attr, val):
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newattr = attr not in self.__dict__
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try:
@@ -468,9 +473,17 @@ def __setattr__(self, attr, val):
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def __getitem__(self, indx):
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obj = ndarray.__getitem__(self, indx)
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if (isinstance(obj, ndarray) and obj.dtype.isbuiltin):
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return obj.view(ndarray)
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return obj
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# copy behavior of getattr, except that here
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# we might also be returning a single element
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if isinstance(obj, ndarray):
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if obj.dtype.fields:
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return obj.view(dtype=(self.dtype.type, obj.dtype.descr))
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else:
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return obj.view(type=ndarray)
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else:
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# return a single element
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return obj
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def __repr__(self) :
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ret = ndarray.__repr__(self)
@@ -489,8 +502,6 @@ def field(self, attr, val=None):
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obj = self.getfield(*res)
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if obj.dtype.fields:
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return obj
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if obj.dtype.char in 'SU':
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return obj.view(chararray)
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return obj.view(ndarray)
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else:
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return self.setfield(val, *res)
@@ -601,7 +612,7 @@ def fromrecords(recList, dtype=None, shape=None, formats=None, names=None,
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>>> r.col1
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array([456, 2])
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>>> r.col2
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chararray(['dbe', 'de'],
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array(['dbe', 'de'],
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dtype='|S3')
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>>> import pickle
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>>> print pickle.loads(pickle.dumps(r))

‎numpy/core/tests/test_records.py‎

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@@ -124,6 +124,28 @@ def test_fromrecords_with_explicit_dtype(self):
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assert_equal(a.b, ['a', 'bbb'])
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assert_equal(a[-1].b, 'bbb')
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def test_recarray_stringtypes(self):
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# Issue #3993
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a = np.array([('abc ', 1), ('abc', 2)],
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dtype=[('foo', 'S4'), ('bar', int)])
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a = a.view(np.recarray)
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assert_equal(a.foo[0] == a.foo[1], False)
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def test_recarray_returntypes(self):
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a = np.rec.array([('abc ', (1,1), 1), ('abc', (2,3), 1)],
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dtype=[('foo', 'S4'),
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('bar', [('A', int), ('B', int)]),
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('baz', int)])
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assert_equal(type(a.foo), np.ndarray)
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assert_equal(type(a['foo']), np.ndarray)
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assert_equal(type(a.bar), np.recarray)
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assert_equal(type(a['bar']), np.recarray)
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assert_equal(a.bar.dtype.type, np.record)
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assert_equal(type(a.baz), np.ndarray)
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assert_equal(type(a['baz']), np.ndarray)
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assert_equal(type(a[0].bar), np.record)
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assert_equal(a[0].bar.A, 1)
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class TestRecord(TestCase):
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def setUp(self):

‎numpy/doc/structured_arrays.py‎

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@@ -268,6 +268,10 @@
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>>> type(recordarr.bar)
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<class 'numpy.core.records.recarray'>
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Note that if a field has the same name as an ndarray attribute, the ndarray
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attribute takes precedence. Such fields will be inaccessible by attribute but
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may still be accessed by index.
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Partial Attribute Access
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------------------------
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