MAINT: Remove implicit inheritance from object class (#15236)

Inheriting from object was necessary for Python 2 compatibility to use
new-style classes. In Python 3, this is unnecessary as there are no
old-style classes.

Dropping the object is more idiomatic Python.

11 files changed, 56 insertions, 56 deletions

diff --git a/numpy/ma/core.py b/numpy/ma/core.py
index 3fa0d63b3..d51d8e6ec 100644
--- a/numpy/ma/core.py
+++ b/numpy/ma/core.py
@@ -798,7 +798,7 @@ ufunc_domain = {}
 ufunc_fills = {}
 
 
-class _DomainCheckInterval(object):
+class _DomainCheckInterval:
     """
     Define a valid interval, so that :
 
@@ -823,7 +823,7 @@ class _DomainCheckInterval(object):
                                     umath.less(x, self.a))
 
 
-class _DomainTan(object):
+class _DomainTan:
     """
     Define a valid interval for the `tan` function, so that:
 
@@ -841,7 +841,7 @@ class _DomainTan(object):
             return umath.less(umath.absolute(umath.cos(x)), self.eps)
 
 
-class _DomainSafeDivide(object):
+class _DomainSafeDivide:
     """
     Define a domain for safe division.
 
@@ -862,7 +862,7 @@ class _DomainSafeDivide(object):
             return umath.absolute(a) * self.tolerance >= umath.absolute(b)
 
 
-class _DomainGreater(object):
+class _DomainGreater:
     """
     DomainGreater(v)(x) is True where x <= v.
 
@@ -878,7 +878,7 @@ class _DomainGreater(object):
             return umath.less_equal(x, self.critical_value)
 
 
-class _DomainGreaterEqual(object):
+class _DomainGreaterEqual:
     """
     DomainGreaterEqual(v)(x) is True where x < v.
 
@@ -894,7 +894,7 @@ class _DomainGreaterEqual(object):
             return umath.less(x, self.critical_value)
 
 
-class _MaskedUFunc(object):
+class _MaskedUFunc:
     def __init__(self, ufunc):
         self.f = ufunc
         self.__doc__ = ufunc.__doc__
@@ -2384,7 +2384,7 @@ def masked_invalid(a, copy=True):
 ###############################################################################
 
 
-class _MaskedPrintOption(object):
+class _MaskedPrintOption:
     """
     Handle the string used to represent missing data in a masked array.
 
@@ -2602,7 +2602,7 @@ def _arraymethod(funcname, onmask=True):
     return wrapped_method
 
 
-class MaskedIterator(object):
+class MaskedIterator:
     """
     Flat iterator object to iterate over masked arrays.
 
@@ -6644,7 +6644,7 @@ ptp.__doc__ = MaskedArray.ptp.__doc__
 ##############################################################################
 
 
-class _frommethod(object):
+class _frommethod:
     """
     Define functions from existing MaskedArray methods.
 
@@ -7978,7 +7978,7 @@ def fromflex(fxarray):
     return masked_array(fxarray['_data'], mask=fxarray['_mask'])
 
 
-class _convert2ma(object):
+class _convert2ma:
 
     """
     Convert functions from numpy to numpy.ma.
diff --git a/numpy/ma/extras.py b/numpy/ma/extras.py
index 221e648c5..31648fb2e 100644
--- a/numpy/ma/extras.py
+++ b/numpy/ma/extras.py
@@ -212,7 +212,7 @@ def masked_all_like(arr):
 #####--------------------------------------------------------------------------
 #---- --- Standard functions ---
 #####--------------------------------------------------------------------------
-class _fromnxfunction(object):
+class _fromnxfunction:
     """
     Defines a wrapper to adapt NumPy functions to masked arrays.
 
diff --git a/numpy/ma/mrecords.py b/numpy/ma/mrecords.py
index 83520d6b9..4ff7866ab 100644
--- a/numpy/ma/mrecords.py
+++ b/numpy/ma/mrecords.py
@@ -85,7 +85,7 @@ def _get_fieldmask(self):
     return fdmask
 
 
-class MaskedRecords(MaskedArray, object):
+class MaskedRecords(MaskedArray):
     """
 
     Attributes
diff --git a/numpy/ma/tests/test_core.py b/numpy/ma/tests/test_core.py
index 31f973e68..458b78580 100644
--- a/numpy/ma/tests/test_core.py
+++ b/numpy/ma/tests/test_core.py
@@ -63,7 +63,7 @@ num_dts = [np.dtype(dt_) for dt_ in '?bhilqBHILQefdgFD']
 num_ids = [dt_.char for dt_ in num_dts]
 
 
-class TestMaskedArray(object):
+class TestMaskedArray:
     # Base test class for MaskedArrays.
 
     def setup(self):
@@ -944,7 +944,7 @@ class TestMaskedArray(object):
         assert_(mx2[0] == 0.)
 
 
-class TestMaskedArrayArithmetic(object):
+class TestMaskedArrayArithmetic:
     # Base test class for MaskedArrays.
 
     def setup(self):
@@ -1713,7 +1713,7 @@ class TestMaskedArrayArithmetic(object):
         assert_equal(a.mask, [0, 0, 0, 0, 1])
 
 
-class TestMaskedArrayAttributes(object):
+class TestMaskedArrayAttributes:
 
     def test_keepmask(self):
         # Tests the keep mask flag
@@ -1889,7 +1889,7 @@ class TestMaskedArrayAttributes(object):
         assert_equal(m._mask, np.ma.nomask)
 
 
-class TestFillingValues(object):
+class TestFillingValues:
 
     def test_check_on_scalar(self):
         # Test _check_fill_value set to valid and invalid values
@@ -2227,7 +2227,7 @@ class TestFillingValues(object):
         assert_equal(a["f1"].fill_value, default_fill_value("eggs"))
 
 
-class TestUfuncs(object):
+class TestUfuncs:
     # Test class for the application of ufuncs on MaskedArrays.
 
     def setup(self):
@@ -2307,7 +2307,7 @@ class TestUfuncs(object):
         assert_raises(TypeError, operator.mul, a, "abc")
         assert_raises(TypeError, operator.truediv, a, "abc")
 
-        class MyClass(object):
+        class MyClass:
             __array_priority__ = a.__array_priority__ + 1
 
             def __mul__(self, other):
@@ -2321,7 +2321,7 @@ class TestUfuncs(object):
         assert_(a * me == "My rmul")
 
         # and that __array_priority__ is respected
-        class MyClass2(object):
+        class MyClass2:
             __array_priority__ = 100
 
             def __mul__(self, other):
@@ -2371,7 +2371,7 @@ class TestUfuncs(object):
             # also check that allclose uses ma ufuncs, to avoid warning
             allclose(m, 0.5)
 
-class TestMaskedArrayInPlaceArithmetics(object):
+class TestMaskedArrayInPlaceArithmetics:
     # Test MaskedArray Arithmetics
 
     def setup(self):
@@ -2873,7 +2873,7 @@ class TestMaskedArrayInPlaceArithmetics(object):
                 assert_equal(len(w), 0, "Failed on type=%s." % t)
 
 
-class TestMaskedArrayMethods(object):
+class TestMaskedArrayMethods:
     # Test class for miscellaneous MaskedArrays methods.
     def setup(self):
         # Base data definition.
@@ -3580,7 +3580,7 @@ class TestMaskedArrayMethods(object):
         assert_equal(xd.data, x.diagonal().data)
 
 
-class TestMaskedArrayMathMethods(object):
+class TestMaskedArrayMathMethods:
 
     def setup(self):
         # Base data definition.
@@ -3858,7 +3858,7 @@ class TestMaskedArrayMathMethods(object):
         assert_equal(a.max(1), [3, 6])
 
 
-class TestMaskedArrayMathMethodsComplex(object):
+class TestMaskedArrayMathMethodsComplex:
     # Test class for miscellaneous MaskedArrays methods.
     def setup(self):
         # Base data definition.
@@ -3911,7 +3911,7 @@ class TestMaskedArrayMathMethodsComplex(object):
                                 mX[:, k].compressed().std())
 
 
-class TestMaskedArrayFunctions(object):
+class TestMaskedArrayFunctions:
     # Test class for miscellaneous functions.
 
     def setup(self):
@@ -4550,7 +4550,7 @@ class TestMaskedArrayFunctions(object):
         assert_equal(test, masked_equal([-1, -1, -1, -1, -1], -1))
 
 
-class TestMaskedFields(object):
+class TestMaskedFields:
 
     def setup(self):
         ilist = [1, 2, 3, 4, 5]
@@ -4712,7 +4712,7 @@ class TestMaskedFields(object):
             assert_equal(len(rec), len(self.data['ddtype']))
 
 
-class TestMaskedObjectArray(object):
+class TestMaskedObjectArray:
 
     def test_getitem(self):
         arr = np.ma.array([None, None])
@@ -4760,7 +4760,7 @@ class TestMaskedObjectArray(object):
         assert_(arr[0] is np.ma.masked)
 
 
-class TestMaskedView(object):
+class TestMaskedView:
 
     def setup(self):
         iterator = list(zip(np.arange(10), np.random.rand(10)))
@@ -4838,7 +4838,7 @@ class TestMaskedView(object):
         assert_(not isinstance(test, MaskedArray))
 
 
-class TestOptionalArgs(object):
+class TestOptionalArgs:
     def test_ndarrayfuncs(self):
         # test axis arg behaves the same as ndarray (including multiple axes)
 
@@ -4925,7 +4925,7 @@ class TestOptionalArgs(object):
         assert_raises(np.AxisError, count, np.ma.array(1), axis=1)
 
 
-class TestMaskedConstant(object):
+class TestMaskedConstant:
     def _do_add_test(self, add):
         # sanity check
         assert_(add(np.ma.masked, 1) is np.ma.masked)
@@ -5042,7 +5042,7 @@ class TestMaskedConstant(object):
         assert_raises(AttributeError, setattr, np.ma.masked, 'dtype', np.int64)
 
 
-class TestMaskedWhereAliases(object):
+class TestMaskedWhereAliases:
 
     # TODO: Test masked_object, masked_equal, ...
 
diff --git a/numpy/ma/tests/test_deprecations.py b/numpy/ma/tests/test_deprecations.py
index 7f44a2176..14f697375 100644
--- a/numpy/ma/tests/test_deprecations.py
+++ b/numpy/ma/tests/test_deprecations.py
@@ -6,7 +6,7 @@ from numpy.testing import assert_warns
 from numpy.ma.testutils import assert_equal
 from numpy.ma.core import MaskedArrayFutureWarning
 
-class TestArgsort(object):
+class TestArgsort:
     """ gh-8701 """
     def _test_base(self, argsort, cls):
         arr_0d = np.array(1).view(cls)
@@ -35,7 +35,7 @@ class TestArgsort(object):
         return self._test_base(np.ma.MaskedArray.argsort, np.ma.MaskedArray)
 
 
-class TestMinimumMaximum(object):
+class TestMinimumMaximum:
     def test_minimum(self):
         assert_warns(DeprecationWarning, np.ma.minimum, np.ma.array([1, 2]))
 
diff --git a/numpy/ma/tests/test_extras.py b/numpy/ma/tests/test_extras.py
index c36bcbbbb..1c8610625 100644
--- a/numpy/ma/tests/test_extras.py
+++ b/numpy/ma/tests/test_extras.py
@@ -32,7 +32,7 @@ from numpy.ma.extras import (
     )
 
 
-class TestGeneric(object):
+class TestGeneric:
     #
     def test_masked_all(self):
         # Tests masked_all
@@ -140,7 +140,7 @@ class TestGeneric(object):
         assert_equal(test, [])
 
 
-class TestAverage(object):
+class TestAverage:
     # Several tests of average. Why so many ? Good point...
     def test_testAverage1(self):
         # Test of average.
@@ -271,7 +271,7 @@ class TestAverage(object):
         assert_almost_equal(wav1.imag, expected1.imag)
 
 
-class TestConcatenator(object):
+class TestConcatenator:
     # Tests for mr_, the equivalent of r_ for masked arrays.
 
     def test_1d(self):
@@ -315,7 +315,7 @@ class TestConcatenator(object):
         assert_equal(actual.data[:2], [1, 2])
 
 
-class TestNotMasked(object):
+class TestNotMasked:
     # Tests notmasked_edges and notmasked_contiguous.
 
     def test_edges(self):
@@ -385,7 +385,7 @@ class TestNotMasked(object):
         ])
 
 
-class TestCompressFunctions(object):
+class TestCompressFunctions:
 
     def test_compress_nd(self):
         # Tests compress_nd
@@ -650,7 +650,7 @@ class TestCompressFunctions(object):
         assert_equal(a, res)
 
 
-class TestApplyAlongAxis(object):
+class TestApplyAlongAxis:
     # Tests 2D functions
     def test_3d(self):
         a = arange(12.).reshape(2, 2, 3)
@@ -672,7 +672,7 @@ class TestApplyAlongAxis(object):
         assert_equal(xa, [[2, 5], [8, 11]])
 
 
-class TestApplyOverAxes(object):
+class TestApplyOverAxes:
     # Tests apply_over_axes
     def test_basic(self):
         a = arange(24).reshape(2, 3, 4)
@@ -685,7 +685,7 @@ class TestApplyOverAxes(object):
         assert_equal(test, ctrl)
 
 
-class TestMedian(object):
+class TestMedian:
     def test_pytype(self):
         r = np.ma.median([[np.inf, np.inf], [np.inf, np.inf]], axis=-1)
         assert_equal(r, np.inf)
@@ -1064,7 +1064,7 @@ class TestMedian(object):
         assert_(type(np.ma.median(o.astype(object))), float)
 
 
-class TestCov(object):
+class TestCov:
 
     def setup(self):
         self.data = array(np.random.rand(12))
@@ -1131,7 +1131,7 @@ class TestCov(object):
                              x.shape[0] / frac))
 
 
-class TestCorrcoef(object):
+class TestCorrcoef:
 
     def setup(self):
         self.data = array(np.random.rand(12))
@@ -1238,7 +1238,7 @@ class TestCorrcoef(object):
                                 control[:-1, :-1])
 
 
-class TestPolynomial(object):
+class TestPolynomial:
     #
     def test_polyfit(self):
         # Tests polyfit
@@ -1296,7 +1296,7 @@ class TestPolynomial(object):
             assert_almost_equal(a, a_)
 
 
-class TestArraySetOps(object):
+class TestArraySetOps:
 
     def test_unique_onlist(self):
         # Test unique on list
@@ -1528,7 +1528,7 @@ class TestArraySetOps(object):
         assert_array_equal(setdiff1d(a, b), np.array(['c']))
 
 
-class TestShapeBase(object):
+class TestShapeBase:
 
     def test_atleast_2d(self):
         # Test atleast_2d
@@ -1584,7 +1584,7 @@ class TestShapeBase(object):
         assert_equal(b.mask.shape, b.data.shape)
 
 
-class TestStack(object):
+class TestStack:
 
     def test_stack_1d(self):
         a = masked_array([0, 1, 2], mask=[0, 1, 0])
diff --git a/numpy/ma/tests/test_mrecords.py b/numpy/ma/tests/test_mrecords.py
index 14d39d949..c2f859273 100644
--- a/numpy/ma/tests/test_mrecords.py
+++ b/numpy/ma/tests/test_mrecords.py
@@ -24,7 +24,7 @@ from numpy.ma.testutils import (
 from numpy.compat import pickle
 
 
-class TestMRecords(object):
+class TestMRecords:
 
     ilist = [1, 2, 3, 4, 5]
     flist = [1.1, 2.2, 3.3, 4.4, 5.5]
@@ -346,7 +346,7 @@ class TestMRecords(object):
                                       dtype=mult.dtype))
 
 
-class TestView(object):
+class TestView:
 
     def setup(self):
         (a, b) = (np.arange(10), np.random.rand(10))
@@ -384,7 +384,7 @@ class TestView(object):
 
 
 ##############################################################################
-class TestMRecordsImport(object):
+class TestMRecordsImport:
 
     _a = ma.array([1, 2, 3], mask=[0, 0, 1], dtype=int)
     _b = ma.array([1.1, 2.2, 3.3], mask=[0, 0, 1], dtype=float)
diff --git a/numpy/ma/tests/test_old_ma.py b/numpy/ma/tests/test_old_ma.py
index 5d5046c09..96c7e3609 100644
--- a/numpy/ma/tests/test_old_ma.py
+++ b/numpy/ma/tests/test_old_ma.py
@@ -31,7 +31,7 @@ def eq(v, w, msg=''):
     return result
 
 
-class TestMa(object):
+class TestMa:
 
     def setup(self):
         x = np.array([1., 1., 1., -2., pi/2.0, 4., 5., -10., 10., 1., 2., 3.])
@@ -698,7 +698,7 @@ class TestMa(object):
         assert_equal(b[1].shape, ())
 
 
-class TestUfuncs(object):
+class TestUfuncs:
     def setup(self):
         self.d = (array([1.0, 0, -1, pi / 2] * 2, mask=[0, 1] + [0] * 6),
                   array([1.0, 0, -1, pi / 2] * 2, mask=[1, 0] + [0] * 6),)
@@ -763,7 +763,7 @@ class TestUfuncs(object):
             assert_(eq(nonzero(x), [0]))
 
 
-class TestArrayMethods(object):
+class TestArrayMethods:
 
     def setup(self):
         x = np.array([8.375, 7.545, 8.828, 8.5, 1.757, 5.928,
diff --git a/numpy/ma/tests/test_regression.py b/numpy/ma/tests/test_regression.py
index 32e8e30c1..9f3368489 100644
--- a/numpy/ma/tests/test_regression.py
+++ b/numpy/ma/tests/test_regression.py
@@ -4,7 +4,7 @@ from numpy.testing import (
     )
 
 
-class TestRegression(object):
+class TestRegression:
     def test_masked_array_create(self):
         # Ticket #17
         x = np.ma.masked_array([0, 1, 2, 3, 0, 4, 5, 6],
diff --git a/numpy/ma/tests/test_subclassing.py b/numpy/ma/tests/test_subclassing.py
index 781079371..02aeebd17 100644
--- a/numpy/ma/tests/test_subclassing.py
+++ b/numpy/ma/tests/test_subclassing.py
@@ -78,7 +78,7 @@ msubarray = MSubArray
 # and overrides __array_wrap__, updating the info dict, to check that this
 # doesn't get destroyed by MaskedArray._update_from.  But this one also needs
 # its own iterator...
-class CSAIterator(object):
+class CSAIterator:
     """
     Flat iterator object that uses its own setter/getter
     (works around ndarray.flat not propagating subclass setters/getters
@@ -152,7 +152,7 @@ class ComplicatedSubArray(SubArray):
         return obj
 
 
-class TestSubclassing(object):
+class TestSubclassing:
     # Test suite for masked subclasses of ndarray.
 
     def setup(self):
diff --git a/numpy/ma/timer_comparison.py b/numpy/ma/timer_comparison.py
index fc63c18b5..83bd7852e 100644
--- a/numpy/ma/timer_comparison.py
+++ b/numpy/ma/timer_comparison.py
@@ -13,7 +13,7 @@ np.seterr(all='ignore')
 pi = np.pi
 
 
-class ModuleTester(object):
+class ModuleTester:
     def __init__(self, module):
         self.module = module
         self.allequal = module.allequal