test_regression.py

from __future__ import division, absolute_import, print_function

import pickle
import sys
import platform
import gc
import copy
import warnings
import tempfile
from os import path
from io import BytesIO

import numpy as np
from numpy.testing import (
        run_module_suite, TestCase, assert_, assert_equal,
        assert_almost_equal, assert_array_equal, assert_array_almost_equal,
        assert_raises, assert_warns, dec
        )
from numpy.testing.utils import _assert_valid_refcount
from numpy.compat import asbytes, asunicode, asbytes_nested, long, sixu

rlevel = 1

class TestRegression(TestCase):
    def test_invalid_round(self,level=rlevel):
        """Ticket #3"""
        v = 4.7599999999999998
        assert_array_equal(np.array([v]), np.array(v))

    def test_mem_empty(self,level=rlevel):
        """Ticket #7"""
        np.empty((1,), dtype=[('x', np.int64)])

    def test_pickle_transposed(self,level=rlevel):
        """Ticket #16"""
        a = np.transpose(np.array([[2, 9], [7, 0], [3, 8]]))
        f = BytesIO()
        pickle.dump(a, f)
        f.seek(0)
        b = pickle.load(f)
        f.close()
        assert_array_equal(a, b)

    def test_typeNA(self,level=rlevel):
        """Ticket #31"""
        assert_equal(np.typeNA[np.int64], 'Int64')
        assert_equal(np.typeNA[np.uint64], 'UInt64')

    def test_dtype_names(self,level=rlevel):
        """Ticket #35"""
        dt = np.dtype([(('name', 'label'), np.int32, 3)])

    def test_reduce(self,level=rlevel):
        """Ticket #40"""
        assert_almost_equal(np.add.reduce([1., .5], dtype=None), 1.5)

    def test_zeros_order(self,level=rlevel):
        """Ticket #43"""
        np.zeros([3], int, 'C')
        np.zeros([3], order='C')
        np.zeros([3], int, order='C')

    def test_asarray_with_order(self,level=rlevel):
        """Check that nothing is done when order='F' and array C/F-contiguous"""
        a = np.ones(2)
        assert_(a is np.asarray(a, order='F'))

    def test_ravel_with_order(self,level=rlevel):
        """Check that ravel works when order='F' and array C/F-contiguous"""
        a = np.ones(2)
        assert_(not a.ravel('F').flags.owndata)

    def test_sort_bigendian(self,level=rlevel):
        """Ticket #47"""
        a = np.linspace(0, 10, 11)
        c = a.astype(np.dtype('<f8'))
        c.sort()
        assert_array_almost_equal(c, a)

    def test_negative_nd_indexing(self,level=rlevel):
        """Ticket #49"""
        c = np.arange(125).reshape((5, 5, 5))
        origidx = np.array([-1, 0, 1])
        idx = np.array(origidx)
        c[idx]
        assert_array_equal(idx, origidx)

    def test_char_dump(self,level=rlevel):
        """Ticket #50"""
        f = BytesIO()
        ca = np.char.array(np.arange(1000, 1010), itemsize=4)
        ca.dump(f)
        f.seek(0)
        ca = np.load(f)
        f.close()

    def test_noncontiguous_fill(self,level=rlevel):
        """Ticket #58."""
        a = np.zeros((5, 3))
        b = a[:, :2,]
        def rs():
            b.shape = (10,)
        self.assertRaises(AttributeError, rs)

    def test_bool(self,level=rlevel):
        """Ticket #60"""
        x = np.bool_(1)

    def test_indexing1(self,level=rlevel):
        """Ticket #64"""
        descr = [('x', [('y', [('z', 'c16', (2,)),]),]),]
        buffer = ((([6j, 4j],),),)
        h = np.array(buffer, dtype=descr)
        h['x']['y']['z']

    def test_indexing2(self,level=rlevel):
        """Ticket #65"""
        descr = [('x', 'i4', (2,))]
        buffer = ([3, 2],)
        h = np.array(buffer, dtype=descr)
        h['x']

    def test_round(self,level=rlevel):
        """Ticket #67"""
        x = np.array([1+2j])
        assert_almost_equal(x**(-1), [1/(1+2j)])

    def test_scalar_compare(self,level=rlevel):
        """Ticket #72"""
        a = np.array(['test', 'auto'])
        assert_array_equal(a == 'auto', np.array([False, True]))
        self.assertTrue(a[1] == 'auto')
        self.assertTrue(a[0] != 'auto')
        b = np.linspace(0, 10, 11)
        self.assertTrue(b != 'auto')
        self.assertTrue(b[0] != 'auto')

    def test_unicode_swapping(self,level=rlevel):
        """Ticket #79"""
        ulen = 1
        ucs_value = sixu('\U0010FFFF')
        ua = np.array([[[ucs_value*ulen]*2]*3]*4, dtype='U%s' % ulen)
        ua2 = ua.newbyteorder()

    def test_object_array_fill(self,level=rlevel):
        """Ticket #86"""
        x = np.zeros(1, 'O')
        x.fill([])

    def test_mem_dtype_align(self,level=rlevel):
        """Ticket #93"""
        self.assertRaises(TypeError, np.dtype,
                              {'names':['a'],'formats':['foo']}, align=1)

    @dec.knownfailureif((sys.version_info[0] >= 3) or
                        (sys.platform == "win32" and platform.architecture()[0] == "64bit"),
                        "numpy.intp('0xff', 16) not supported on Py3, "
                        "as it does not inherit from Python int")
    def test_intp(self,level=rlevel):
        """Ticket #99"""
        i_width = np.int_(0).nbytes*2 - 1
        np.intp('0x' + 'f'*i_width, 16)
        self.assertRaises(OverflowError, np.intp, '0x' + 'f'*(i_width+1), 16)
        self.assertRaises(ValueError, np.intp, '0x1', 32)
        assert_equal(255, np.intp('0xFF', 16))
        assert_equal(1024, np.intp(1024))

    def test_endian_bool_indexing(self,level=rlevel):
        """Ticket #105"""
        a = np.arange(10., dtype='>f8')
        b = np.arange(10., dtype='<f8')
        xa = np.where((a>2) & (a<6))
        xb = np.where((b>2) & (b<6))
        ya = ((a>2) & (a<6))
        yb = ((b>2) & (b<6))
        assert_array_almost_equal(xa, ya.nonzero())
        assert_array_almost_equal(xb, yb.nonzero())
        assert_(np.all(a[ya] > 0.5))
        assert_(np.all(b[yb] > 0.5))

    def test_endian_where(self,level=rlevel):
        """GitHuB issue #369"""
        net = np.zeros(3, dtype='>f4')
        net[1] = 0.00458849
        net[2] = 0.605202
        max_net = net.max()
        test = np.where(net <= 0., max_net, net)
        correct = np.array([ 0.60520202,  0.00458849,  0.60520202])
        assert_array_almost_equal(test, correct)

    def test_endian_recarray(self,level=rlevel):
        """Ticket #2185"""
        dt = np.dtype([
               ('head', '>u4'),
               ('data', '>u4', 2),
            ])
        buf = np.recarray(1, dtype=dt)
        buf[0]['head'] = 1
        buf[0]['data'][:] = [1, 1]

        h = buf[0]['head']
        d = buf[0]['data'][0]
        buf[0]['head'] = h
        buf[0]['data'][0] = d
        assert_(buf[0]['head'] == 1)

    def test_mem_dot(self,level=rlevel):
        """Ticket #106"""
        x = np.random.randn(0, 1)
        y = np.random.randn(10, 1)
        # Dummy array to detect bad memory access:
        _z = np.ones(10)
        _dummy = np.empty((0, 10))
        z = np.lib.stride_tricks.as_strided(_z, _dummy.shape, _dummy.strides)
        np.dot(x, np.transpose(y), out=z)
        assert_equal(_z, np.ones(10))
        # Do the same for the built-in dot:
        np.core.multiarray.dot(x, np.transpose(y), out=z)
        assert_equal(_z, np.ones(10))

    def test_arange_endian(self,level=rlevel):
        """Ticket #111"""
        ref = np.arange(10)
        x = np.arange(10, dtype='<f8')
        assert_array_equal(ref, x)
        x = np.arange(10, dtype='>f8')
        assert_array_equal(ref, x)

#    Longfloat support is not consistent enough across
#     platforms for this test to be meaningful.
#    def test_longfloat_repr(self,level=rlevel):
#        """Ticket #112"""
#        if np.longfloat(0).itemsize > 8:
#            a = np.exp(np.array([1000],dtype=np.longfloat))
#            assert_(str(a)[1:9] == str(a[0])[:8])

    def test_argmax(self,level=rlevel):
        """Ticket #119"""
        a = np.random.normal(0, 1, (4, 5, 6, 7, 8))
        for i in range(a.ndim):
            aargmax = a.argmax(i)

    def test_mem_divmod(self,level=rlevel):
        """Ticket #126"""
        for i in range(10):
            divmod(np.array([i])[0], 10)


    def test_hstack_invalid_dims(self,level=rlevel):
        """Ticket #128"""
        x = np.arange(9).reshape((3, 3))
        y = np.array([0, 0, 0])
        self.assertRaises(ValueError, np.hstack, (x, y))

    def test_squeeze_type(self,level=rlevel):
        """Ticket #133"""
        a = np.array([3])
        b = np.array(3)
        assert_(type(a.squeeze()) is np.ndarray)
        assert_(type(b.squeeze()) is np.ndarray)

    def test_add_identity(self,level=rlevel):
        """Ticket #143"""
        assert_equal(0, np.add.identity)

    def test_numpy_float_python_long_addition(self):
        # Check that numpy float and python longs can be added correctly.
        a = np.float_(23.) + 2**135
        assert_equal(a, 23. + 2**135)

    def test_binary_repr_0(self,level=rlevel):
        """Ticket #151"""
        assert_equal('0', np.binary_repr(0))

    def test_rec_iterate(self,level=rlevel):
        """Ticket #160"""
        descr = np.dtype([('i', int), ('f', float), ('s', '|S3')])
        x = np.rec.array([(1, 1.1, '1.0'),
                         (2, 2.2, '2.0')], dtype=descr)
        x[0].tolist()
        [i for i in x[0]]

    def test_unicode_string_comparison(self,level=rlevel):
        """Ticket #190"""
        a = np.array('hello', np.unicode_)
        b = np.array('world')
        a == b

    def test_tostring_FORTRANORDER_discontiguous(self,level=rlevel):
        """Fix in r2836"""
        # Create discontiguous Fortran-ordered array
        x = np.array(np.random.rand(3, 3), order='F')[:, :2]
        assert_array_almost_equal(x.ravel(), np.fromstring(x.tostring()))

    def test_flat_assignment(self,level=rlevel):
        """Correct behaviour of ticket #194"""
        x = np.empty((3, 1))
        x.flat = np.arange(3)
        assert_array_almost_equal(x, [[0], [1], [2]])
        x.flat = np.arange(3, dtype=float)
        assert_array_almost_equal(x, [[0], [1], [2]])

    def test_broadcast_flat_assignment(self,level=rlevel):
        """Ticket #194"""
        x = np.empty((3, 1))
        def bfa(): x[:] = np.arange(3)
        def bfb(): x[:] = np.arange(3, dtype=float)
        self.assertRaises(ValueError, bfa)
        self.assertRaises(ValueError, bfb)

    def test_nonarray_assignment(self):
        # See also Issue gh-2870, test for nonarray assignment
        # and equivalent unsafe casted array assignment
        a = np.arange(10)
        b = np.ones(10, dtype=bool)
        r = np.arange(10)
        def assign(a, b, c):
            a[b] = c
        assert_raises(ValueError, assign, a, b, np.nan)
        a[b] = np.array(np.nan) # but not this.
        assert_raises(ValueError, assign, a, r, np.nan)
        a[r] = np.array(np.nan)

    def test_unpickle_dtype_with_object(self,level=rlevel):
        """Implemented in r2840"""
        dt = np.dtype([('x', int), ('y', np.object_), ('z', 'O')])
        f = BytesIO()
        pickle.dump(dt, f)
        f.seek(0)
        dt_ = pickle.load(f)
        f.close()
        assert_equal(dt, dt_)

    def test_mem_array_creation_invalid_specification(self,level=rlevel):
        """Ticket #196"""
        dt = np.dtype([('x', int), ('y', np.object_)])
        # Wrong way
        self.assertRaises(ValueError, np.array, [1, 'object'], dt)
        # Correct way
        np.array([(1, 'object')], dt)

    def test_recarray_single_element(self,level=rlevel):
        """Ticket #202"""
        a = np.array([1, 2, 3], dtype=np.int32)
        b = a.copy()
        r = np.rec.array(a, shape=1, formats=['3i4'], names=['d'])
        assert_array_equal(a, b)
        assert_equal(a, r[0][0])

    def test_zero_sized_array_indexing(self,level=rlevel):
        """Ticket #205"""
        tmp = np.array([])
        def index_tmp(): tmp[np.array(10)]
        self.assertRaises(IndexError, index_tmp)

    def test_chararray_rstrip(self,level=rlevel):
        """Ticket #222"""
        x = np.chararray((1,), 5)
        x[0] = asbytes('a   ')
        x = x.rstrip()
        assert_equal(x[0], asbytes('a'))

    def test_object_array_shape(self,level=rlevel):
        """Ticket #239"""
        assert_equal(np.array([[1, 2], 3, 4], dtype=object).shape, (3,))
        assert_equal(np.array([[1, 2], [3, 4]], dtype=object).shape, (2, 2))
        assert_equal(np.array([(1, 2), (3, 4)], dtype=object).shape, (2, 2))
        assert_equal(np.array([], dtype=object).shape, (0,))
        assert_equal(np.array([[], [], []], dtype=object).shape, (3, 0))
        assert_equal(np.array([[3, 4], [5, 6], None], dtype=object).shape, (3,))

    def test_mem_around(self,level=rlevel):
        """Ticket #243"""
        x = np.zeros((1,))
        y = [0]
        decimal = 6
        np.around(abs(x-y), decimal) <= 10.0**(-decimal)

    def test_character_array_strip(self,level=rlevel):
        """Ticket #246"""
        x = np.char.array(("x", "x ", "x  "))
        for c in x: assert_equal(c, "x")

    def test_lexsort(self,level=rlevel):
        """Lexsort memory error"""
        v = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
        assert_equal(np.lexsort(v), 0)

    def test_pickle_dtype(self,level=rlevel):
        """Ticket #251"""
        pickle.dumps(np.float)

    def test_swap_real(self, level=rlevel):
        """Ticket #265"""
        assert_equal(np.arange(4, dtype='>c8').imag.max(), 0.0)
        assert_equal(np.arange(4, dtype='<c8').imag.max(), 0.0)
        assert_equal(np.arange(4, dtype='>c8').real.max(), 3.0)
        assert_equal(np.arange(4, dtype='<c8').real.max(), 3.0)

    def test_object_array_from_list(self, level=rlevel):
        """Ticket #270"""
        a = np.array([1, 'A', None])

    def test_multiple_assign(self, level=rlevel):
        """Ticket #273"""
        a = np.zeros((3, 1), int)
        a[[1, 2]] = 1

    def test_empty_array_type(self, level=rlevel):
        assert_equal(np.array([]).dtype, np.zeros(0).dtype)

    def test_void_copyswap(self, level=rlevel):
        dt = np.dtype([('one', '<i4'), ('two', '<i4')])
        x = np.array((1, 2), dtype=dt)
        x = x.byteswap()
        assert_(x['one'] > 1 and x['two'] > 2)

    def test_method_args(self, level=rlevel):
        # Make sure methods and functions have same default axis
        # keyword and arguments
        funcs1= ['argmax', 'argmin', 'sum', ('product', 'prod'),
                 ('sometrue', 'any'),
                 ('alltrue', 'all'), 'cumsum', ('cumproduct', 'cumprod'),
                 'ptp', 'cumprod', 'prod', 'std', 'var', 'mean',
                 'round', 'min', 'max', 'argsort', 'sort']
        funcs2 = ['compress', 'take', 'repeat']

        for func in funcs1:
            arr = np.random.rand(8, 7)
            arr2 = arr.copy()
            if isinstance(func, tuple):
                func_meth = func[1]
                func = func[0]
            else:
                func_meth = func
            res1 = getattr(arr, func_meth)()
            res2 = getattr(np, func)(arr2)
            if res1 is None:
                assert_(abs(arr-res2).max() < 1e-8, func)
            else:
                assert_(abs(res1-res2).max() < 1e-8, func)

        for func in funcs2:
            arr1 = np.random.rand(8, 7)
            arr2 = np.random.rand(8, 7)
            res1 = None
            if func == 'compress':
                arr1 = arr1.ravel()
                res1 = getattr(arr2, func)(arr1)
            else:
                arr2 = (15*arr2).astype(int).ravel()
            if res1 is None:
                res1 = getattr(arr1, func)(arr2)
            res2 = getattr(np, func)(arr1, arr2)
            assert_(abs(res1-res2).max() < 1e-8, func)

    def test_mem_lexsort_strings(self, level=rlevel):
        """Ticket #298"""
        lst = ['abc', 'cde', 'fgh']
        np.lexsort((lst,))

    def test_fancy_index(self, level=rlevel):
        """Ticket #302"""
        x = np.array([1, 2])[np.array([0])]
        assert_equal(x.shape, (1,))

    def test_recarray_copy(self, level=rlevel):
        """Ticket #312"""
        dt = [('x', np.int16), ('y', np.float64)]
        ra = np.array([(1, 2.3)], dtype=dt)
        rb = np.rec.array(ra, dtype=dt)
        rb['x'] = 2.
        assert_(ra['x'] != rb['x'])

    def test_rec_fromarray(self, level=rlevel):
        """Ticket #322"""
        x1 = np.array([[1, 2], [3, 4], [5, 6]])
        x2 = np.array(['a', 'dd', 'xyz'])
        x3 = np.array([1.1, 2, 3])
        np.rec.fromarrays([x1, x2, x3], formats="(2,)i4,a3,f8")

    def test_object_array_assign(self, level=rlevel):
        x = np.empty((2, 2), object)
        x.flat[2] = (1, 2, 3)
        assert_equal(x.flat[2], (1, 2, 3))

    def test_ndmin_float64(self, level=rlevel):
        """Ticket #324"""
        x = np.array([1, 2, 3], dtype=np.float64)
        assert_equal(np.array(x, dtype=np.float32, ndmin=2).ndim, 2)
        assert_equal(np.array(x, dtype=np.float64, ndmin=2).ndim, 2)

    def test_ndmin_order(self, level=rlevel):
        """Issue #465 and related checks"""
        assert_(np.array([1, 2], order='C', ndmin=3).flags.c_contiguous)
        assert_(np.array([1, 2], order='F', ndmin=3).flags.f_contiguous)
        assert_(np.array(np.ones((2, 2), order='F'), ndmin=3).flags.f_contiguous)
        assert_(np.array(np.ones((2, 2), order='C'), ndmin=3).flags.c_contiguous)

    def test_mem_axis_minimization(self, level=rlevel):
        """Ticket #327"""
        data = np.arange(5)
        data = np.add.outer(data, data)

    def test_mem_float_imag(self, level=rlevel):
        """Ticket #330"""
        np.float64(1.0).imag

    def test_dtype_tuple(self, level=rlevel):
        """Ticket #334"""
        assert_(np.dtype('i4') == np.dtype(('i4', ())))

    def test_dtype_posttuple(self, level=rlevel):
        """Ticket #335"""
        np.dtype([('col1', '()i4')])

    def test_numeric_carray_compare(self, level=rlevel):
        """Ticket #341"""
        assert_equal(np.array(['X'], 'c'), asbytes('X'))

    def test_string_array_size(self, level=rlevel):
        """Ticket #342"""
        self.assertRaises(ValueError,
                              np.array, [['X'], ['X', 'X', 'X']], '|S1')

    def test_dtype_repr(self, level=rlevel):
        """Ticket #344"""
        dt1=np.dtype(('uint32', 2))
        dt2=np.dtype(('uint32', (2,)))
        assert_equal(dt1.__repr__(), dt2.__repr__())

    def test_reshape_order(self, level=rlevel):
        """Make sure reshape order works."""
        a = np.arange(6).reshape(2, 3, order='F')
        assert_equal(a, [[0, 2, 4], [1, 3, 5]])
        a = np.array([[1, 2], [3, 4], [5, 6], [7, 8]])
        b = a[:, 1]
        assert_equal(b.reshape(2, 2, order='F'), [[2, 6], [4, 8]])

    def test_reshape_zero_strides(self, level=rlevel):
        """Issue #380, test reshaping of zero strided arrays"""
        a = np.ones(1)
        a = np.lib.stride_tricks.as_strided(a, shape=(5,), strides=(0,))
        assert_(a.reshape(5, 1).strides[0] == 0)

    def test_reshape_zero_size(self, level=rlevel):
        """Github Issue #2700, setting shape failed for 0-sized arrays"""
        a = np.ones((0, 2))
        a.shape = (-1, 2)

    # Cannot test if NPY_RELAXED_STRIDES_CHECKING changes the strides.
    # With NPY_RELAXED_STRIDES_CHECKING the test becomes superfluous.
    @dec.skipif(np.ones(1).strides[0] == np.iinfo(np.intp).max)
    def test_reshape_trailing_ones_strides(self):
        # Github issue gh-2949, bad strides for trailing ones of new shape
        a = np.zeros(12, dtype=np.int32)[::2] # not contiguous
        strides_c = (16, 8, 8, 8)
        strides_f = (8, 24, 48, 48)
        assert_equal(a.reshape(3, 2, 1, 1).strides, strides_c)
        assert_equal(a.reshape(3, 2, 1, 1, order='F').strides, strides_f)
        assert_equal(np.array(0, dtype=np.int32).reshape(1, 1).strides, (4, 4))

    def test_repeat_discont(self, level=rlevel):
        """Ticket #352"""
        a = np.arange(12).reshape(4, 3)[:, 2]
        assert_equal(a.repeat(3), [2, 2, 2, 5, 5, 5, 8, 8, 8, 11, 11, 11])

    def test_array_index(self, level=rlevel):
        """Make sure optimization is not called in this case."""
        a = np.array([1, 2, 3])
        a2 = np.array([[1, 2, 3]])
        assert_equal(a[np.where(a==3)], a2[np.where(a2==3)])

    def test_object_argmax(self, level=rlevel):
        a = np.array([1, 2, 3], dtype=object)
        assert_(a.argmax() == 2)

    def test_recarray_fields(self, level=rlevel):
        """Ticket #372"""
        dt0 = np.dtype([('f0', 'i4'), ('f1', 'i4')])
        dt1 = np.dtype([('f0', 'i8'), ('f1', 'i8')])
        for a in [np.array([(1, 2), (3, 4)], "i4,i4"),
                  np.rec.array([(1, 2), (3, 4)], "i4,i4"),
                  np.rec.array([(1, 2), (3, 4)]),
                  np.rec.fromarrays([(1, 2), (3, 4)], "i4,i4"),
                  np.rec.fromarrays([(1, 2), (3, 4)])]:
            assert_(a.dtype in [dt0, dt1])

    def test_random_shuffle(self, level=rlevel):
        """Ticket #374"""
        a = np.arange(5).reshape((5, 1))
        b = a.copy()
        np.random.shuffle(b)
        assert_equal(np.sort(b, axis=0), a)

    def test_refcount_vdot(self, level=rlevel):
        """Changeset #3443"""
        _assert_valid_refcount(np.vdot)

    def test_startswith(self, level=rlevel):
        ca = np.char.array(['Hi', 'There'])
        assert_equal(ca.startswith('H'), [True, False])

    def test_noncommutative_reduce_accumulate(self, level=rlevel):
        """Ticket #413"""
        tosubtract = np.arange(5)
        todivide = np.array([2.0, 0.5, 0.25])
        assert_equal(np.subtract.reduce(tosubtract), -10)
        assert_equal(np.divide.reduce(todivide), 16.0)
        assert_array_equal(np.subtract.accumulate(tosubtract),
            np.array([0, -1, -3, -6, -10]))
        assert_array_equal(np.divide.accumulate(todivide),
            np.array([2., 4., 16.]))

    def test_convolve_empty(self, level=rlevel):
        """Convolve should raise an error for empty input array."""
        self.assertRaises(ValueError, np.convolve, [], [1])
        self.assertRaises(ValueError, np.convolve, [1], [])

    def test_multidim_byteswap(self, level=rlevel):
        """Ticket #449"""
        r=np.array([(1, (0, 1, 2))], dtype="i2,3i2")
        assert_array_equal(r.byteswap(),
                           np.array([(256, (0, 256, 512))], r.dtype))

    def test_string_NULL(self, level=rlevel):
        """Changeset 3557"""
        assert_equal(np.array("a\x00\x0b\x0c\x00").item(),
                     'a\x00\x0b\x0c')

    def test_junk_in_string_fields_of_recarray(self, level=rlevel):
        """Ticket #483"""
        r = np.array([[asbytes('abc')]], dtype=[('var1', '|S20')])
        assert_(asbytes(r['var1'][0][0]) == asbytes('abc'))

    def test_take_output(self, level=rlevel):
        """Ensure that 'take' honours output parameter."""
        x = np.arange(12).reshape((3, 4))
        a = np.take(x, [0, 2], axis=1)
        b = np.zeros_like(a)
        np.take(x, [0, 2], axis=1, out=b)
        assert_array_equal(a, b)

    def test_take_object_fail(self):
        # Issue gh-3001
        d = 123.
        a = np.array([d, 1], dtype=object)
        ref_d = sys.getrefcount(d)
        try:
            a.take([0, 100])
        except IndexError:
            pass
        assert_(ref_d == sys.getrefcount(d))

    def test_array_str_64bit(self, level=rlevel):
        """Ticket #501"""
        s = np.array([1, np.nan], dtype=np.float64)
        with np.errstate(all='raise'):
            sstr = np.array_str(s)

    def test_frompyfunc_endian(self, level=rlevel):
        """Ticket #503"""
        from math import radians
        uradians = np.frompyfunc(radians, 1, 1)
        big_endian = np.array([83.4, 83.5], dtype='>f8')
        little_endian = np.array([83.4, 83.5], dtype='<f8')
        assert_almost_equal(uradians(big_endian).astype(float),
                            uradians(little_endian).astype(float))

    def test_mem_string_arr(self, level=rlevel):
        """Ticket #514"""
        s = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
        t = []
        np.hstack((t, s ))

    def test_arr_transpose(self, level=rlevel):
        """Ticket #516"""
        x = np.random.rand(*(2,)*16)
        y = x.transpose(list(range(16)))

    def test_string_mergesort(self, level=rlevel):
        """Ticket #540"""
        x = np.array(['a']*32)
        assert_array_equal(x.argsort(kind='m'), np.arange(32))

    def test_argmax_byteorder(self, level=rlevel):
        """Ticket #546"""
        a = np.arange(3, dtype='>f')
        assert_(a[a.argmax()] == a.max())

    def test_rand_seed(self, level=rlevel):
        """Ticket #555"""
        for l in np.arange(4):
            np.random.seed(l)

    def test_mem_deallocation_leak(self, level=rlevel):
        """Ticket #562"""
        a = np.zeros(5, dtype=float)
        b = np.array(a, dtype=float)
        del a, b

    def test_mem_on_invalid_dtype(self):
        "Ticket #583"
        self.assertRaises(ValueError, np.fromiter, [['12', ''], ['13', '']], str)

    def test_dot_negative_stride(self, level=rlevel):
        """Ticket #588"""
        x = np.array([[1, 5, 25, 125., 625]])
        y = np.array([[20.], [160.], [640.], [1280.], [1024.]])
        z = y[::-1].copy()
        y2 = y[::-1]
        assert_equal(np.dot(x, z), np.dot(x, y2))

    def test_object_casting(self, level=rlevel):
        # This used to trigger the object-type version of
        # the bitwise_or operation, because float64 -> object
        # casting succeeds
        def rs():
            x = np.ones([484, 286])
            y = np.zeros([484, 286])
            x |= y
        self.assertRaises(TypeError, rs)

    def test_unicode_scalar(self, level=rlevel):
        """Ticket #600"""
        x = np.array(["DROND", "DROND1"], dtype="U6")
        el = x[1]
        new = pickle.loads(pickle.dumps(el))
        assert_equal(new, el)

    def test_arange_non_native_dtype(self, level=rlevel):
        """Ticket #616"""
        for T in ('>f4', '<f4'):
            dt = np.dtype(T)
            assert_equal(np.arange(0, dtype=dt).dtype, dt)
            assert_equal(np.arange(0.5, dtype=dt).dtype, dt)
            assert_equal(np.arange(5, dtype=dt).dtype, dt)

    def test_bool_indexing_invalid_nr_elements(self, level=rlevel):
        s = np.ones(10, dtype=float)
        x = np.array((15,), dtype=float)
        def ia(x, s, v): x[(s>0)]=v
        self.assertRaises(ValueError, ia, x, s, np.zeros(9, dtype=float))
        self.assertRaises(ValueError, ia, x, s, np.zeros(11, dtype=float))

    def test_mem_scalar_indexing(self, level=rlevel):
        """Ticket #603"""
        x = np.array([0], dtype=float)
        index = np.array(0, dtype=np.int32)
        x[index]

    def test_binary_repr_0_width(self, level=rlevel):
        assert_equal(np.binary_repr(0, width=3), '000')

    def test_fromstring(self, level=rlevel):
        assert_equal(np.fromstring("12:09:09", dtype=int, sep=":"),
                     [12, 9, 9])

    def test_searchsorted_variable_length(self, level=rlevel):
        x = np.array(['a', 'aa', 'b'])
        y = np.array(['d', 'e'])
        assert_equal(x.searchsorted(y), [3, 3])

    def test_string_argsort_with_zeros(self, level=rlevel):
        """Check argsort for strings containing zeros."""
        x = np.fromstring("\x00\x02\x00\x01", dtype="|S2")
        assert_array_equal(x.argsort(kind='m'), np.array([1, 0]))
        assert_array_equal(x.argsort(kind='q'), np.array([1, 0]))

    def test_string_sort_with_zeros(self, level=rlevel):
        """Check sort for strings containing zeros."""
        x = np.fromstring("\x00\x02\x00\x01", dtype="|S2")
        y = np.fromstring("\x00\x01\x00\x02", dtype="|S2")
        assert_array_equal(np.sort(x, kind="q"), y)

    def test_copy_detection_zero_dim(self, level=rlevel):
        """Ticket #658"""
        np.indices((0, 3, 4)).T.reshape(-1, 3)

    def test_flat_byteorder(self, level=rlevel):
        """Ticket #657"""
        x = np.arange(10)
        assert_array_equal(x.astype('>i4'), x.astype('<i4').flat[:])
        assert_array_equal(x.astype('>i4').flat[:], x.astype('<i4'))

    def test_uint64_from_negative(self, level=rlevel) :
        assert_equal(np.uint64(-2), np.uint64(18446744073709551614))

    def test_sign_bit(self, level=rlevel):
        x = np.array([0, -0.0, 0])
        assert_equal(str(np.abs(x)), '[ 0.  0.  0.]')

    def test_flat_index_byteswap(self, level=rlevel):
        for dt in (np.dtype('<i4'), np.dtype('>i4')):
            x = np.array([-1, 0, 1], dtype=dt)
            assert_equal(x.flat[0].dtype, x[0].dtype)

    def test_copy_detection_corner_case(self, level=rlevel):
        """Ticket #658"""
        np.indices((0, 3, 4)).T.reshape(-1, 3)

    # Cannot test if NPY_RELAXED_STRIDES_CHECKING changes the strides.
    # With NPY_RELAXED_STRIDES_CHECKING the test becomes superfluous,
    # 0-sized reshape itself is tested elsewhere.
    @dec.skipif(np.ones(1).strides[0] == np.iinfo(np.intp).max)
    def test_copy_detection_corner_case2(self, level=rlevel):
        """Ticket #771: strides are not set correctly when reshaping 0-sized
        arrays"""
        b = np.indices((0, 3, 4)).T.reshape(-1, 3)
        assert_equal(b.strides, (3 * b.itemsize, b.itemsize))

    def test_object_array_refcounting(self, level=rlevel):
        """Ticket #633"""
        if not hasattr(sys, 'getrefcount'):
            return

        # NB. this is probably CPython-specific

        cnt = sys.getrefcount

        a = object()
        b = object()
        c = object()

        cnt0_a = cnt(a)
        cnt0_b = cnt(b)
        cnt0_c = cnt(c)

        # -- 0d -> 1d broadcasted slice assignment

        arr = np.zeros(5, dtype=np.object_)

        arr[:] = a
        assert_equal(cnt(a), cnt0_a + 5)

        arr[:] = b
        assert_equal(cnt(a), cnt0_a)
        assert_equal(cnt(b), cnt0_b + 5)

        arr[:2] = c
        assert_equal(cnt(b), cnt0_b + 3)
        assert_equal(cnt(c), cnt0_c + 2)

        del arr

        # -- 1d -> 2d broadcasted slice assignment

        arr  = np.zeros((5, 2), dtype=np.object_)
        arr0 = np.zeros(2, dtype=np.object_)

        arr0[0] = a
        assert_(cnt(a) == cnt0_a + 1)
        arr0[1] = b
        assert_(cnt(b) == cnt0_b + 1)

        arr[:,:] = arr0
        assert_(cnt(a) == cnt0_a + 6)
        assert_(cnt(b) == cnt0_b + 6)

        arr[:, 0] = None
        assert_(cnt(a) == cnt0_a + 1)

        del arr, arr0

        # -- 2d copying + flattening

        arr  = np.zeros((5, 2), dtype=np.object_)

        arr[:, 0] = a
        arr[:, 1] = b
        assert_(cnt(a) == cnt0_a + 5)
        assert_(cnt(b) == cnt0_b + 5)

        arr2 = arr.copy()
        assert_(cnt(a) == cnt0_a + 10)
        assert_(cnt(b) == cnt0_b + 10)

        arr2 = arr[:, 0].copy()
        assert_(cnt(a) == cnt0_a + 10)
        assert_(cnt(b) == cnt0_b + 5)

        arr2 = arr.flatten()
        assert_(cnt(a) == cnt0_a + 10)
        assert_(cnt(b) == cnt0_b + 10)

        del arr, arr2

        # -- concatenate, repeat, take, choose

        arr1 = np.zeros((5, 1), dtype=np.object_)
        arr2 = np.zeros((5, 1), dtype=np.object_)

        arr1[...] = a
        arr2[...] = b
        assert_(cnt(a) == cnt0_a + 5)
        assert_(cnt(b) == cnt0_b + 5)

        arr3 = np.concatenate((arr1, arr2))
        assert_(cnt(a) == cnt0_a + 5 + 5)
        assert_(cnt(b) == cnt0_b + 5 + 5)

        arr3 = arr1.repeat(3, axis=0)
        assert_(cnt(a) == cnt0_a + 5 + 3*5)

        arr3 = arr1.take([1, 2, 3], axis=0)
        assert_(cnt(a) == cnt0_a + 5 + 3)

        x = np.array([[0], [1], [0], [1], [1]], int)
        arr3 = x.choose(arr1, arr2)
        assert_(cnt(a) == cnt0_a + 5 + 2)
        assert_(cnt(b) == cnt0_b + 5 + 3)

    def test_mem_custom_float_to_array(self, level=rlevel):
        """Ticket 702"""
        class MyFloat(object):
            def __float__(self):
                return 1.0

        tmp = np.atleast_1d([MyFloat()])
        tmp2 = tmp.astype(float)

    def test_object_array_refcount_self_assign(self, level=rlevel):
        """Ticket #711"""
        class VictimObject(object):
            deleted = False
            def __del__(self):
                self.deleted = True
        d = VictimObject()
        arr = np.zeros(5, dtype=np.object_)
        arr[:] = d
        del d
        arr[:] = arr # refcount of 'd' might hit zero here
        assert_(not arr[0].deleted)
        arr[:] = arr # trying to induce a segfault by doing it again...
        assert_(not arr[0].deleted)

    def test_mem_fromiter_invalid_dtype_string(self, level=rlevel):
        x = [1, 2, 3]
        self.assertRaises(ValueError,
                              np.fromiter, [xi for xi in x], dtype='S')

    def test_reduce_big_object_array(self, level=rlevel):
        """Ticket #713"""
        oldsize = np.setbufsize(10*16)
        a = np.array([None]*161, object)
        assert_(not np.any(a))
        np.setbufsize(oldsize)

    def test_mem_0d_array_index(self, level=rlevel):
        """Ticket #714"""
        np.zeros(10)[np.array(0)]

    def test_floats_from_string(self, level=rlevel):
        """Ticket #640, floats from string"""
        fsingle = np.single('1.234')
        fdouble = np.double('1.234')
        flongdouble = np.longdouble('1.234')
        assert_almost_equal(fsingle, 1.234)
        assert_almost_equal(fdouble, 1.234)
        assert_almost_equal(flongdouble, 1.234)

    def test_nonnative_endian_fill(self, level=rlevel):
        """ Non-native endian arrays were incorrectly filled with scalars before
        r5034.
        """
        if sys.byteorder == 'little':
            dtype = np.dtype('>i4')
        else:
            dtype = np.dtype('<i4')
        x = np.empty([1], dtype=dtype)
        x.fill(1)
        assert_equal(x, np.array([1], dtype=dtype))

    def test_dot_alignment_sse2(self, level=rlevel):
        """Test for ticket #551, changeset r5140"""
        x = np.zeros((30, 40))
        y = pickle.loads(pickle.dumps(x))
        # y is now typically not aligned on a 8-byte boundary
        z = np.ones((1, y.shape[0]))
        # This shouldn't cause a segmentation fault:
        np.dot(z, y)

    def test_astype_copy(self, level=rlevel):
        """Ticket #788, changeset r5155"""
        # The test data file was generated by scipy.io.savemat.
        # The dtype is float64, but the isbuiltin attribute is 0.
        data_dir = path.join(path.dirname(__file__), 'data')
        filename = path.join(data_dir, "astype_copy.pkl")
        if sys.version_info[0] >= 3:
            f = open(filename, 'rb')
            xp = pickle.load(f, encoding='latin1')
            f.close()
        else:
            f = open(filename)
            xp = pickle.load(f)
            f.close()
        xpd = xp.astype(np.float64)
        assert_((xp.__array_interface__['data'][0] !=
                xpd.__array_interface__['data'][0]))

    def test_compress_small_type(self, level=rlevel):
        """Ticket #789, changeset 5217.
        """
        # compress with out argument segfaulted if cannot cast safely
        import numpy as np
        a = np.array([[1, 2], [3, 4]])
        b = np.zeros((2, 1), dtype = np.single)
        try:
            a.compress([True, False], axis = 1, out = b)
            raise AssertionError("compress with an out which cannot be " \
                                 "safely casted should not return "\
                                 "successfully")
        except TypeError:
            pass

    def test_attributes(self, level=rlevel):
        """Ticket #791
        """
        class TestArray(np.ndarray):
            def __new__(cls, data, info):
                result = np.array(data)
                result = result.view(cls)
                result.info = info
                return result
            def __array_finalize__(self, obj):
                self.info = getattr(obj, 'info', '')
        dat = TestArray([[1, 2, 3, 4], [5, 6, 7, 8]], 'jubba')
        assert_(dat.info == 'jubba')
        dat.resize((4, 2))
        assert_(dat.info == 'jubba')
        dat.sort()
        assert_(dat.info == 'jubba')
        dat.fill(2)
        assert_(dat.info == 'jubba')
        dat.put([2, 3, 4], [6, 3, 4])
        assert_(dat.info == 'jubba')
        dat.setfield(4, np.int32, 0)
        assert_(dat.info == 'jubba')
        dat.setflags()
        assert_(dat.info == 'jubba')
        assert_(dat.all(1).info == 'jubba')
        assert_(dat.any(1).info == 'jubba')
        assert_(dat.argmax(1).info == 'jubba')
        assert_(dat.argmin(1).info == 'jubba')
        assert_(dat.argsort(1).info == 'jubba')
        assert_(dat.astype(TestArray).info == 'jubba')
        assert_(dat.byteswap().info == 'jubba')
        assert_(dat.clip(2, 7).info == 'jubba')
        assert_(dat.compress([0, 1, 1]).info == 'jubba')
        assert_(dat.conj().info == 'jubba')
        assert_(dat.conjugate().info == 'jubba')
        assert_(dat.copy().info == 'jubba')
        dat2 = TestArray([2, 3, 1, 0], 'jubba')
        choices = [[0, 1, 2, 3], [10, 11, 12, 13],
                   [20, 21, 22, 23], [30, 31, 32, 33]]
        assert_(dat2.choose(choices).info == 'jubba')
        assert_(dat.cumprod(1).info == 'jubba')
        assert_(dat.cumsum(1).info == 'jubba')
        assert_(dat.diagonal().info == 'jubba')
        assert_(dat.flatten().info == 'jubba')
        assert_(dat.getfield(np.int32, 0).info == 'jubba')
        assert_(dat.imag.info == 'jubba')
        assert_(dat.max(1).info == 'jubba')
        assert_(dat.mean(1).info == 'jubba')
        assert_(dat.min(1).info == 'jubba')
        assert_(dat.newbyteorder().info == 'jubba')
        assert_(dat.nonzero()[0].info == 'jubba')
        assert_(dat.nonzero()[1].info == 'jubba')
        assert_(dat.prod(1).info == 'jubba')
        assert_(dat.ptp(1).info == 'jubba')
        assert_(dat.ravel().info == 'jubba')
        assert_(dat.real.info == 'jubba')
        assert_(dat.repeat(2).info == 'jubba')
        assert_(dat.reshape((2, 4)).info == 'jubba')
        assert_(dat.round().info == 'jubba')
        assert_(dat.squeeze().info == 'jubba')
        assert_(dat.std(1).info == 'jubba')
        assert_(dat.sum(1).info == 'jubba')
        assert_(dat.swapaxes(0, 1).info == 'jubba')
        assert_(dat.take([2, 3, 5]).info == 'jubba')
        assert_(dat.transpose().info == 'jubba')
        assert_(dat.T.info == 'jubba')
        assert_(dat.var(1).info == 'jubba')
        assert_(dat.view(TestArray).info == 'jubba')

    def test_recarray_tolist(self, level=rlevel):
        """Ticket #793, changeset r5215
        """
        # Comparisons fail for NaN, so we can't use random memory
        # for the test.
        buf = np.zeros(40, dtype=np.int8)
        a = np.recarray(2, formats="i4,f8,f8", names="id,x,y", buf=buf)
        b = a.tolist()
        assert_( a[0].tolist() == b[0])
        assert_( a[1].tolist() == b[1])

    def test_nonscalar_item_method(self):
        # Make sure that .item() fails graciously when it should
        a = np.arange(5)
        assert_raises(ValueError, a.item)

    def test_char_array_creation(self, level=rlevel):
        a = np.array('123', dtype='c')
        b = np.array(asbytes_nested(['1', '2', '3']))
        assert_equal(a, b)

    def test_unaligned_unicode_access(self, level=rlevel) :
        """Ticket #825"""
        for i in range(1, 9) :
            msg = 'unicode offset: %d chars'%i
            t = np.dtype([('a', 'S%d'%i), ('b', 'U2')])
            x = np.array([(asbytes('a'), sixu('b'))], dtype=t)
            if sys.version_info[0] >= 3:
                assert_equal(str(x), "[(b'a', 'b')]", err_msg=msg)
            else:
                assert_equal(str(x), "[('a', u'b')]", err_msg=msg)

    def test_sign_for_complex_nan(self, level=rlevel):
        """Ticket 794."""
        with np.errstate(invalid='ignore'):
            C = np.array([-np.inf, -2+1j, 0, 2-1j, np.inf, np.nan])
            have = np.sign(C)
            want = np.array([-1+0j, -1+0j, 0+0j, 1+0j, 1+0j, np.nan])
            assert_equal(have, want)

    def test_for_equal_names(self, level=rlevel):
        """Ticket #674"""
        dt = np.dtype([('foo', float), ('bar', float)])
        a = np.zeros(10, dt)
        b = list(a.dtype.names)
        b[0] = "notfoo"
        a.dtype.names = b
        assert_(a.dtype.names[0] == "notfoo")
        assert_(a.dtype.names[1] == "bar")

    def test_for_object_scalar_creation(self, level=rlevel):
        """Ticket #816"""
        a = np.object_()
        b = np.object_(3)
        b2 = np.object_(3.0)
        c = np.object_([4, 5])
        d = np.object_([None, {}, []])
        assert_(a is None)
        assert_(type(b) is int)
        assert_(type(b2) is float)
        assert_(type(c) is np.ndarray)
        assert_(c.dtype == object)
        assert_(d.dtype == object)

    def test_array_resize_method_system_error(self):
        """Ticket #840 - order should be an invalid keyword."""
        x = np.array([[0, 1], [2, 3]])
        self.assertRaises(TypeError, x.resize, (2, 2), order='C')

    def test_for_zero_length_in_choose(self, level=rlevel):
        "Ticket #882"
        a = np.array(1)
        self.assertRaises(ValueError, lambda x: x.choose([]), a)

    def test_array_ndmin_overflow(self):
        "Ticket #947."
        self.assertRaises(ValueError, lambda: np.array([1], ndmin=33))

    def test_errobj_reference_leak(self, level=rlevel):
        """Ticket #955"""
        with np.errstate(all="ignore"):
            z = int(0)
            p = np.int32(-1)

            gc.collect()
            n_before = len(gc.get_objects())
            z**p  # this shouldn't leak a reference to errobj
            gc.collect()
            n_after = len(gc.get_objects())
            assert_(n_before >= n_after, (n_before, n_after))

    def test_void_scalar_with_titles(self, level=rlevel):
        """No ticket"""
        data = [('john', 4), ('mary', 5)]
        dtype1 = [(('source:yy', 'name'), 'O'), (('source:xx', 'id'), int)]
        arr = np.array(data, dtype=dtype1)
        assert_(arr[0][0] == 'john')
        assert_(arr[0][1] == 4)

    def test_void_scalar_constructor(self):
        #Issue #1550

        #Create test string data, construct void scalar from data and assert
        #that void scalar contains original data.
        test_string = np.array("test")
        test_string_void_scalar = np.core.multiarray.scalar(
            np.dtype(("V", test_string.dtype.itemsize)), test_string.tostring())

        assert_(test_string_void_scalar.view(test_string.dtype) == test_string)

        #Create record scalar, construct from data and assert that
        #reconstructed scalar is correct.
        test_record = np.ones((), "i,i")
        test_record_void_scalar = np.core.multiarray.scalar(
            test_record.dtype, test_record.tostring())

        assert_(test_record_void_scalar == test_record)

        #Test pickle and unpickle of void and record scalars
        assert_(pickle.loads(pickle.dumps(test_string)) == test_string)
        assert_(pickle.loads(pickle.dumps(test_record)) == test_record)

    def test_blasdot_uninitialized_memory(self):
        """Ticket #950"""
        for m in [0, 1, 2]:
            for n in [0, 1, 2]:
                for k in range(3):
                    # Try to ensure that x->data contains non-zero floats
                    x = np.array([123456789e199], dtype=np.float64)
                    x.resize((m, 0))
                    y = np.array([123456789e199], dtype=np.float64)
                    y.resize((0, n))

                    # `dot` should just return zero (m,n) matrix
                    z = np.dot(x, y)
                    assert_(np.all(z == 0))
                    assert_(z.shape == (m, n))

    def test_zeros(self):
        """Regression test for #1061."""
        # Set a size which cannot fit into a 64 bits signed integer
        sz = 2 ** 64
        good = 'Maximum allowed dimension exceeded'
        try:
            np.empty(sz)
        except ValueError as e:
            if not str(e) == good:
                self.fail("Got msg '%s', expected '%s'" % (e, good))
        except Exception as e:
            self.fail("Got exception of type %s instead of ValueError" % type(e))

    def test_huge_arange(self):
        """Regression test for #1062."""
        # Set a size which cannot fit into a 64 bits signed integer
        sz = 2 ** 64
        good = 'Maximum allowed size exceeded'
        try:
            a = np.arange(sz)
            self.assertTrue(np.size == sz)
        except ValueError as e:
            if not str(e) == good:
                self.fail("Got msg '%s', expected '%s'" % (e, good))
        except Exception as e:
            self.fail("Got exception of type %s instead of ValueError" % type(e))

    def test_fromiter_bytes(self):
        """Ticket #1058"""
        a = np.fromiter(list(range(10)), dtype='b')
        b = np.fromiter(list(range(10)), dtype='B')
        assert_(np.alltrue(a == np.array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])))
        assert_(np.alltrue(b == np.array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])))

    def test_array_from_sequence_scalar_array(self):
        """Ticket #1078: segfaults when creating an array with a sequence of 0d
        arrays."""
        a = np.array((np.ones(2), np.array(2)))
        assert_equal(a.shape, (2,))
        assert_equal(a.dtype, np.dtype(object))
        assert_equal(a[0], np.ones(2))
        assert_equal(a[1], np.array(2))

        a = np.array(((1,), np.array(1)))
        assert_equal(a.shape, (2,))
        assert_equal(a.dtype, np.dtype(object))
        assert_equal(a[0], (1,))
        assert_equal(a[1], np.array(1))

    def test_array_from_sequence_scalar_array2(self):
        """Ticket #1081: weird array with strange input..."""
        t = np.array([np.array([]), np.array(0, object)])
        assert_equal(t.shape, (2,))
        assert_equal(t.dtype, np.dtype(object))

    def test_array_too_big(self):
        """Ticket #1080."""
        assert_raises(ValueError, np.zeros, [975]*7, np.int8)
        assert_raises(ValueError, np.zeros, [26244]*5, np.int8)

    def test_dtype_keyerrors_(self):
        """Ticket #1106."""
        dt = np.dtype([('f1', np.uint)])
        assert_raises(KeyError, dt.__getitem__, "f2")
        assert_raises(IndexError, dt.__getitem__, 1)
        assert_raises(ValueError, dt.__getitem__, 0.0)

    def test_lexsort_buffer_length(self):
        """Ticket #1217, don't segfault."""
        a = np.ones(100, dtype=np.int8)
        b = np.ones(100, dtype=np.int32)
        i = np.lexsort((a[::-1], b))
        assert_equal(i, np.arange(100, dtype=np.int))

    def test_object_array_to_fixed_string(self):
        """Ticket #1235."""
        a = np.array(['abcdefgh', 'ijklmnop'], dtype=np.object_)
        b = np.array(a, dtype=(np.str_, 8))
        assert_equal(a, b)
        c = np.array(a, dtype=(np.str_, 5))
        assert_equal(c, np.array(['abcde', 'ijklm']))
        d = np.array(a, dtype=(np.str_, 12))
        assert_equal(a, d)
        e = np.empty((2, ), dtype=(np.str_, 8))
        e[:] = a[:]
        assert_equal(a, e)

    def test_unicode_to_string_cast(self):
        """Ticket #1240."""
        a = np.array(
                [   [sixu('abc'), sixu('\u03a3')],
                    [sixu('asdf'), sixu('erw')]
                ], dtype='U')
        def fail():
            b = np.array(a, 'S4')
        self.assertRaises(UnicodeEncodeError, fail)

    def test_mixed_string_unicode_array_creation(self):
        a = np.array(['1234', sixu('123')])
        assert_(a.itemsize == 16)
        a = np.array([sixu('123'), '1234'])
        assert_(a.itemsize == 16)
        a = np.array(['1234', sixu('123'), '12345'])
        assert_(a.itemsize == 20)
        a = np.array([sixu('123'), '1234', sixu('12345')])
        assert_(a.itemsize == 20)
        a = np.array([sixu('123'), '1234', sixu('1234')])
        assert_(a.itemsize == 16)

    def test_misaligned_objects_segfault(self):
        """Ticket #1198 and #1267"""
        a1 = np.zeros((10,), dtype='O,c')
        a2 = np.array(['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j'], 'S10')
        a1['f0'] = a2
        r = repr(a1)
        np.argmax(a1['f0'])
        a1['f0'][1] = "FOO"
        a1['f0'] = "FOO"
        a3 = np.array(a1['f0'], dtype='S')
        np.nonzero(a1['f0'])
        a1.sort()
        a4 = copy.deepcopy(a1)

    def test_misaligned_scalars_segfault(self):
        """Ticket #1267"""
        s1 = np.array(('a', 'Foo'), dtype='c,O')
        s2 = np.array(('b', 'Bar'), dtype='c,O')
        s1['f1'] = s2['f1']
        s1['f1'] = 'Baz'

    def test_misaligned_dot_product_objects(self):
        """Ticket #1267"""
        # This didn't require a fix, but it's worth testing anyway, because
        # it may fail if .dot stops enforcing the arrays to be BEHAVED
        a = np.array([[(1, 'a'), (0, 'a')], [(0, 'a'), (1, 'a')]], dtype='O,c')
        b = np.array([[(4, 'a'), (1, 'a')], [(2, 'a'), (2, 'a')]], dtype='O,c')
        np.dot(a['f0'], b['f0'])

    def test_byteswap_complex_scalar(self):
        """Ticket #1259 and gh-441"""
        for dtype in [np.dtype('<'+t) for t in np.typecodes['Complex']]:
            z = np.array([2.2-1.1j], dtype)
            x = z[0] # always native-endian
            y = x.byteswap()
            if x.dtype.byteorder == z.dtype.byteorder:
                # little-endian machine
                assert_equal(x, np.fromstring(y.tostring(), dtype=dtype.newbyteorder()))
            else:
                # big-endian machine
                assert_equal(x, np.fromstring(y.tostring(), dtype=dtype))
            # double check real and imaginary parts:
            assert_equal(x.real, y.real.byteswap())
            assert_equal(x.imag, y.imag.byteswap())

    def test_structured_arrays_with_objects1(self):
        """Ticket #1299"""
        stra = 'aaaa'
        strb = 'bbbb'
        x = np.array([[(0, stra), (1, strb)]], 'i8,O')
        x[x.nonzero()] = x.ravel()[:1]
        assert_(x[0, 1] == x[0, 0])

    def test_structured_arrays_with_objects2(self):
        """Ticket #1299 second test"""
        stra = 'aaaa'
        strb = 'bbbb'
        numb = sys.getrefcount(strb)
        numa = sys.getrefcount(stra)
        x = np.array([[(0, stra), (1, strb)]], 'i8,O')
        x[x.nonzero()] = x.ravel()[:1]
        assert_(sys.getrefcount(strb) == numb)
        assert_(sys.getrefcount(stra) == numa + 2)

    def test_duplicate_title_and_name(self):
        """Ticket #1254"""
        def func():
            x = np.dtype([(('a', 'a'), 'i'), ('b', 'i')])
        self.assertRaises(ValueError, func)

    def test_signed_integer_division_overflow(self):
        """Ticket #1317."""
        def test_type(t):
            min = np.array([np.iinfo(t).min])
            min //= -1

        with np.errstate(divide="ignore"):
            for t in (np.int8, np.int16, np.int32, np.int64, np.int, np.long):
                test_type(t)

    def test_buffer_hashlib(self):
        try:
            from hashlib import md5
        except ImportError:
            from md5 import new as md5

        x = np.array([1, 2, 3], dtype=np.dtype('<i4'))
        assert_equal(md5(x).hexdigest(), '2a1dd1e1e59d0a384c26951e316cd7e6')

    def test_numeric_handleError(self):
        """Ticket #1405"""
        from numpy import numarray
        # Just make sure this doesn't throw an exception
        numarray.handleError(0, "")

    def test_0d_string_scalar(self):
        # Bug #1436; the following should succeed
        np.asarray('x', '>c')

    def test_log1p_compiler_shenanigans(self):
        # Check if log1p is behaving on 32 bit intel systems.
        assert_(np.isfinite(np.log1p(np.exp2(-53))))

    def test_fromiter_comparison(self, level=rlevel):
        a = np.fromiter(list(range(10)), dtype='b')
        b = np.fromiter(list(range(10)), dtype='B')
        assert_(np.alltrue(a == np.array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])))
        assert_(np.alltrue(b == np.array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])))

    def test_fromstring_crash(self):
        # Ticket #1345: the following should not cause a crash
        np.fromstring(asbytes('aa, aa, 1.0'), sep=',')

    def test_ticket_1539(self):
        dtypes = [x for x in np.typeDict.values()
                  if (issubclass(x, np.number)
                      and not issubclass(x, np.timedelta64))]
        a = np.array([], dtypes[0])
        failures = []
        # ignore complex warnings
        with warnings.catch_warnings():
            warnings.simplefilter('ignore', np.ComplexWarning)
            for x in dtypes:
                b = a.astype(x)
                for y in dtypes:
                    c = a.astype(y)
                    try:
                        np.dot(b, c)
                    except TypeError as e:
                        failures.append((x, y))
        if failures:
            raise AssertionError("Failures: %r" % failures)

    def test_ticket_1538(self):
        x = np.finfo(np.float32)
        for name in 'eps epsneg max min resolution tiny'.split():
            assert_equal(type(getattr(x, name)), np.float32,
                         err_msg=name)

    def test_ticket_1434(self):
        # Check that the out= argument in var and std has an effect
        data = np.array(((1, 2, 3), (4, 5, 6), (7, 8, 9)))
        out = np.zeros((3,))

        ret = data.var(axis=1, out=out)
        assert_(ret is out)
        assert_array_equal(ret, data.var(axis=1))

        ret = data.std(axis=1, out=out)
        assert_(ret is out)
        assert_array_equal(ret, data.std(axis=1))

    def test_complex_nan_maximum(self):
        cnan = complex(0, np.nan)
        assert_equal(np.maximum(1, cnan), cnan)

    def test_subclass_int_tuple_assignment(self):
        # ticket #1563
        class Subclass(np.ndarray):
            def __new__(cls, i):
                return np.ones((i,)).view(cls)
        x = Subclass(5)
        x[(0,)] = 2 # shouldn't raise an exception
        assert_equal(x[0], 2)

    def test_ufunc_no_unnecessary_views(self):
        # ticket #1548
        class Subclass(np.ndarray):
            pass
        x = np.array([1, 2, 3]).view(Subclass)
        y = np.add(x, x, x)
        assert_equal(id(x), id(y))

    def test_take_refcount(self):
        # ticket #939
        a = np.arange(16, dtype=np.float)
        a.shape = (4, 4)
        lut = np.ones((5 + 3, 4), np.float)
        rgba = np.empty(shape=a.shape + (4,), dtype=lut.dtype)
        c1 = sys.getrefcount(rgba)
        try:
            lut.take(a, axis=0, mode='clip', out=rgba)
        except TypeError:
            pass
        c2 = sys.getrefcount(rgba)
        assert_equal(c1, c2)

    def test_fromfile_tofile_seeks(self):
        # On Python 3, tofile/fromfile used to get (#1610) the Python
        # file handle out of sync
        f0 = tempfile.NamedTemporaryFile()
        f = f0.file
        f.write(np.arange(255, dtype='u1').tostring())

        f.seek(20)
        ret = np.fromfile(f, count=4, dtype='u1')
        assert_equal(ret, np.array([20, 21, 22, 23], dtype='u1'))
        assert_equal(f.tell(), 24)

        f.seek(40)
        np.array([1, 2, 3], dtype='u1').tofile(f)
        assert_equal(f.tell(), 43)

        f.seek(40)
        data = f.read(3)
        assert_equal(data, asbytes("\x01\x02\x03"))

        f.seek(80)
        f.read(4)
        data = np.fromfile(f, dtype='u1', count=4)
        assert_equal(data, np.array([84, 85, 86, 87], dtype='u1'))

        f.close()

    def test_complex_scalar_warning(self):
        for tp in [np.csingle, np.cdouble, np.clongdouble]:
            x = tp(1+2j)
            assert_warns(np.ComplexWarning, float, x)
            with warnings.catch_warnings():
                warnings.simplefilter('ignore')
                assert_equal(float(x), float(x.real))

    def test_complex_scalar_complex_cast(self):
        for tp in [np.csingle, np.cdouble, np.clongdouble]:
            x = tp(1+2j)
            assert_equal(complex(x), 1+2j)

    def test_complex_boolean_cast(self):
        """Ticket #2218"""
        for tp in [np.csingle, np.cdouble, np.clongdouble]:
            x = np.array([0, 0+0.5j, 0.5+0j], dtype=tp)
            assert_equal(x.astype(bool), np.array([0, 1, 1], dtype=bool))
            assert_(np.any(x))
            assert_(np.all(x[1:]))

    def test_uint_int_conversion(self):
        x = 2**64 - 1
        assert_equal(int(np.uint64(x)), x)

    def test_duplicate_field_names_assign(self):
        ra = np.fromiter(((i*3, i*2) for i in range(10)), dtype='i8,f8')
        ra.dtype.names = ('f1', 'f2')
        rep = repr(ra) # should not cause a segmentation fault
        assert_raises(ValueError, setattr, ra.dtype, 'names', ('f1', 'f1'))

    def test_eq_string_and_object_array(self):
        # From e-mail thread "__eq__ with str and object" (Keith Goodman)
        a1 = np.array(['a', 'b'], dtype=object)
        a2 = np.array(['a', 'c'])
        assert_array_equal(a1 == a2, [True, False])
        assert_array_equal(a2 == a1, [True, False])

    def test_nonzero_byteswap(self):
        a = np.array([0x80000000, 0x00000080, 0], dtype=np.uint32)
        a.dtype = np.float32
        assert_equal(a.nonzero()[0], [1])
        a = a.byteswap().newbyteorder()
        assert_equal(a.nonzero()[0], [1]) # [0] if nonzero() ignores swap

    def test_find_common_type_boolean(self):
        # Ticket #1695
        assert_(np.find_common_type([], ['?', '?']) == '?')

    def test_empty_mul(self):
        a = np.array([1.])
        a[1:1] *= 2
        assert_equal(a, [1.])

    def test_array_side_effect(self):
        assert_equal(np.dtype('S10').itemsize, 10)

        A = np.array([['abc', 2], ['long   ', '0123456789']], dtype=np.string_)

        # This was throwing an exception because in ctors.c,
        # discover_itemsize was calling PyObject_Length without checking
        # the return code.  This failed to get the length of the number 2,
        # and the exception hung around until something checked
        # PyErr_Occurred() and returned an error.
        assert_equal(np.dtype('S10').itemsize, 10)

    def test_any_float(self):
        # all and any for floats
        a = np.array([0.1, 0.9])
        assert_(np.any(a))
        assert_(np.all(a))

    def test_large_float_sum(self):
        a = np.arange(10000, dtype='f')
        assert_equal(a.sum(dtype='d'), a.astype('d').sum())

    def test_ufunc_casting_out(self):
        a = np.array(1.0, dtype=np.float32)
        b = np.array(1.0, dtype=np.float64)
        c = np.array(1.0, dtype=np.float32)
        np.add(a, b, out=c)
        assert_equal(c, 2.0)

    def test_array_scalar_contiguous(self):
        # Array scalars are both C and Fortran contiguous
        assert_(np.array(1.0).flags.c_contiguous)
        assert_(np.array(1.0).flags.f_contiguous)
        assert_(np.array(np.float32(1.0)).flags.c_contiguous)
        assert_(np.array(np.float32(1.0)).flags.f_contiguous)

    def test_squeeze_contiguous(self):
        """Similar to GitHub issue #387"""
        a = np.zeros((1, 2)).squeeze()
        b = np.zeros((2, 2, 2), order='F')[:,:, ::2].squeeze()
        assert_(a.flags.c_contiguous)
        assert_(a.flags.f_contiguous)
        assert_(b.flags.f_contiguous)

    def test_reduce_contiguous(self):
        """GitHub issue #387"""
        a = np.add.reduce(np.zeros((2, 1, 2)), (0, 1))
        b = np.add.reduce(np.zeros((2, 1, 2)), 1)
        assert_(a.flags.c_contiguous)
        assert_(a.flags.f_contiguous)
        assert_(b.flags.c_contiguous)

    def test_object_array_self_reference(self):
        # Object arrays with references to themselves can cause problems
        a = np.array(0, dtype=object)
        a[()] = a
        assert_raises(TypeError, int, a)
        assert_raises(TypeError, long, a)
        assert_raises(TypeError, float, a)
        assert_raises(TypeError, oct, a)
        assert_raises(TypeError, hex, a)

        # This was causing a to become like the above
        a = np.array(0, dtype=object)
        a[...] += 1
        assert_equal(a, 1)

    def test_object_array_self_copy(self):
        # An object array being copied into itself DECREF'ed before INCREF'ing
        # causing segmentation faults (gh-3787) 
        a = np.array(object(), dtype=object)
        np.copyto(a, a)
        assert_equal(sys.getrefcount(a[()]), 2)
        a[()].__class__ # will segfault if object was deleted

    def test_zerosize_accumulate(self):
        "Ticket #1733"
        x = np.array([[42, 0]], dtype=np.uint32)
        assert_equal(np.add.accumulate(x[:-1, 0]), [])

    def test_objectarray_setfield(self):
        # Setfield directly manipulates the raw array data,
        # so is invalid for object arrays.
        x = np.array([1, 2, 3], dtype=object)
        assert_raises(RuntimeError, x.setfield, 4, np.int32, 0)

    def test_setting_rank0_string(self):
        "Ticket #1736"
        s1 = asbytes("hello1")
        s2 = asbytes("hello2")
        a = np.zeros((), dtype="S10")
        a[()] = s1
        assert_equal(a, np.array(s1))
        a[()] = np.array(s2)
        assert_equal(a, np.array(s2))

        a = np.zeros((), dtype='f4')
        a[()] = 3
        assert_equal(a, np.array(3))
        a[()] = np.array(4)
        assert_equal(a, np.array(4))

    def test_string_astype(self):
        "Ticket #1748"
        s1 = asbytes('black')
        s2 = asbytes('white')
        s3 = asbytes('other')
        a = np.array([[s1], [s2], [s3]])
        assert_equal(a.dtype, np.dtype('S5'))
        b = a.astype(np.dtype('S0'))
        assert_equal(b.dtype, np.dtype('S5'))

    def test_ticket_1756(self):
        """Ticket #1756 """
        s = asbytes('0123456789abcdef')
        a = np.array([s]*5)
        for i in range(1, 17):
            a1 = np.array(a, "|S%d"%i)
            a2 = np.array([s[:i]]*5)
            assert_equal(a1, a2)

    def test_fields_strides(self):
        "Ticket #1760"
        r=np.fromstring('abcdefghijklmnop'*4*3, dtype='i4,(2,3)u2')
        assert_equal(r[0:3:2]['f1'], r['f1'][0:3:2])
        assert_equal(r[0:3:2]['f1'][0], r[0:3:2][0]['f1'])
        assert_equal(r[0:3:2]['f1'][0][()], r[0:3:2][0]['f1'][()])
        assert_equal(r[0:3:2]['f1'][0].strides, r[0:3:2][0]['f1'].strides)

    def test_alignment_update(self):
        """Check that alignment flag is updated on stride setting"""
        a = np.arange(10)
        assert_(a.flags.aligned)
        a.strides = 3
        assert_(not a.flags.aligned)

    def test_ticket_1770(self):
        "Should not segfault on python 3k"
        import numpy as np
        try:
            a = np.zeros((1,), dtype=[('f1', 'f')])
            a['f1'] = 1
            a['f2'] = 1
        except ValueError:
            pass
        except:
            raise AssertionError

    def test_ticket_1608(self):
        "x.flat shouldn't modify data"
        x = np.array([[1, 2], [3, 4]]).T
        y = np.array(x.flat)
        assert_equal(x, [[1, 3], [2, 4]])

    def test_pickle_string_overwrite(self):
        import re

        data = np.array([1], dtype='b')
        blob = pickle.dumps(data, protocol=1)
        data = pickle.loads(blob)

        # Check that loads does not clobber interned strings
        s = re.sub("a(.)", "\x01\\1", "a_")
        assert_equal(s[0], "\x01")
        data[0] = 0xbb
        s = re.sub("a(.)", "\x01\\1", "a_")
        assert_equal(s[0], "\x01")

    def test_pickle_bytes_overwrite(self):
        if sys.version_info[0] >= 3:
            data = np.array([1], dtype='b')
            data = pickle.loads(pickle.dumps(data))
            data[0] = 0xdd
            bytestring = "\x01  ".encode('ascii')
            assert_equal(bytestring[0:1], '\x01'.encode('ascii'))

    def test_structured_type_to_object(self):
        a_rec = np.array([(0, 1), (3, 2)], dtype='i4,i8')
        a_obj = np.empty((2,), dtype=object)
        a_obj[0] = (0, 1)
        a_obj[1] = (3, 2)
        # astype records -> object
        assert_equal(a_rec.astype(object), a_obj)
        # '=' records -> object
        b = np.empty_like(a_obj)
        b[...] = a_rec
        assert_equal(b, a_obj)
        # '=' object -> records
        b = np.empty_like(a_rec)
        b[...] = a_obj
        assert_equal(b, a_rec)

    def test_assign_obj_listoflists(self):
        # Ticket # 1870
        # The inner list should get assigned to the object elements
        a = np.zeros(4, dtype=object)
        b = a.copy()
        a[0] = [1]
        a[1] = [2]
        a[2] = [3]
        a[3] = [4]
        b[...] = [[1], [2], [3], [4]]
        assert_equal(a, b)
        # The first dimension should get broadcast
        a = np.zeros((2, 2), dtype=object)
        a[...] = [[1, 2]]
        assert_equal(a, [[1, 2], [1, 2]])

    def test_memoryleak(self):
        # Ticket #1917 - ensure that array data doesn't leak
        for i in range(1000):
            # 100MB times 1000 would give 100GB of memory usage if it leaks
            a = np.empty((100000000,), dtype='i1')
            del a

    def test_ufunc_reduce_memoryleak(self):
        a = np.arange(6)
        acnt = sys.getrefcount(a)
        res = np.add.reduce(a)
        assert_equal(sys.getrefcount(a), acnt)

    def test_search_sorted_invalid_arguments(self):
        # Ticket #2021, should not segfault.
        x = np.arange(0, 4, dtype='datetime64[D]')
        assert_raises(TypeError, x.searchsorted, 1)

    def test_string_truncation(self):
        # Ticket #1990 - Data can be truncated in creation of an array from a
        # mixed sequence of numeric values and strings
        for val in [True, 1234, 123.4, complex(1, 234)]:
            for tostr in [asunicode, asbytes]:
                b = np.array([val, tostr('xx')])
                assert_equal(tostr(b[0]), tostr(val))
                b = np.array([tostr('xx'), val])
                assert_equal(tostr(b[1]), tostr(val))

                # test also with longer strings
                b = np.array([val, tostr('xxxxxxxxxx')])
                assert_equal(tostr(b[0]), tostr(val))
                b = np.array([tostr('xxxxxxxxxx'), val])
                assert_equal(tostr(b[1]), tostr(val))

    def test_string_truncation_ucs2(self):
        # Ticket #2081. Python compiled with two byte unicode
        # can lead to truncation if itemsize is not properly
        # adjusted for Numpy's four byte unicode.
        if sys.version_info[0] >= 3:
            a = np.array(['abcd'])
        else:
            a = np.array([sixu('abcd')])
        assert_equal(a.dtype.itemsize, 16)

    def test_unique_stable(self):
        # Ticket #2063 must always choose stable sort for argsort to
        # get consistent results
        v = np.array(([0]*5 + [1]*6 + [2]*6)*4)
        res = np.unique(v, return_index=True)
        tgt = (np.array([0, 1, 2]), np.array([ 0,  5, 11]))
        assert_equal(res, tgt)

    def test_unicode_alloc_dealloc_match(self):
        # Ticket #1578, the mismatch only showed up when running
        # python-debug for python versions >= 2.7, and then as
        # a core dump and error message.
        a = np.array(['abc'], dtype=np.unicode)[0]
        del a

    def test_refcount_error_in_clip(self):
        # Ticket #1588
        a = np.zeros((2,), dtype='>i2').clip(min=0)
        x = a + a
        # This used to segfault:
        y = str(x)
        # Check the final string:
        assert_(y == "[0 0]")

    def test_searchsorted_wrong_dtype(self):
        # Ticket #2189, it used to segfault, so we check that it raises the
        # proper exception.
        a = np.array([('a', 1)], dtype='S1, int')
        assert_raises(TypeError, np.searchsorted, a, 1.2)
        # Ticket #2066, similar problem:
        dtype = np.format_parser(['i4', 'i4'], [], [])
        a = np.recarray((2, ), dtype)
        assert_raises(TypeError, np.searchsorted, a, 1)

    def test_complex64_alignment(self):
        # Issue gh-2668 (trac 2076), segfault on sparc due to misalignment
        dtt = np.complex64
        arr = np.arange(10, dtype=dtt)
        # 2D array
        arr2 = np.reshape(arr, (2, 5))
        # Fortran write followed by (C or F) read caused bus error
        data_str = arr2.tostring('F')
        data_back = np.ndarray(arr2.shape,
                              arr2.dtype,
                              buffer=data_str,
                              order='F')
        assert_array_equal(arr2, data_back)

    def test_structured_count_nonzero(self):
        arr = np.array([0, 1]).astype('i4, (2)i4')[:1]
        count = np.count_nonzero(arr)
        assert_equal(count, 0)

    def test_copymodule_preserves_f_contiguity(self):
        a = np.empty((2, 2), order='F')
        b = copy.copy(a)
        c = copy.deepcopy(a)
        assert_(b.flags.fortran)
        assert_(b.flags.f_contiguous)
        assert_(c.flags.fortran)
        assert_(c.flags.f_contiguous)

    def test_fortran_order_buffer(self):
        import numpy as np
        a = np.array([['Hello', 'Foob']], dtype='<U5', order='F')
        arr = np.ndarray(shape=[1, 2, 5], dtype='<U1', buffer=a)
        arr2 = np.array([[[sixu('H'), sixu('e'), sixu('l'), sixu('l'), sixu('o')],
                          [sixu('F'), sixu('o'), sixu('o'), sixu('b'), sixu('')]]])
        assert_array_equal(arr, arr2)

if __name__ == "__main__":
    run_module_suite()