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import py
from pypy.module.micronumpy.test.test_base import BaseNumpyAppTest
class AppTestNDIter(BaseNumpyAppTest):
def test_type(self):
import numpy as np
assert type(np.nditer) is type
assert np.nditer.__name__ == 'nditer'
assert np.nditer.__module__ == 'numpy'
try:
class Sub(np.nditer):
pass
except TypeError as e:
assert "not an acceptable base" in str(e)
else:
assert False
def test_basic(self):
from numpy import arange, nditer, ndarray
a = arange(6).reshape(2,3)
i = nditer(a)
r = []
for x in i:
assert type(x) is ndarray
assert x.base is i
assert x.shape == ()
assert x.strides == ()
exc = raises(ValueError, "x[()] = 42")
assert str(exc.value) == 'assignment destination is read-only'
r.append(x)
assert r == [0, 1, 2, 3, 4, 5]
r = []
for x in nditer(a.T):
r.append(x)
assert r == [0, 1, 2, 3, 4, 5]
def test_order(self):
from numpy import arange, nditer
a = arange(6).reshape(2,3)
r = []
for x in nditer(a, order='C'):
r.append(x)
assert r == [0, 1, 2, 3, 4, 5]
r = []
for x in nditer(a, order='F'):
r.append(x)
assert r == [0, 3, 1, 4, 2, 5]
def test_readwrite(self):
from numpy import arange, nditer, ndarray
a = arange(6).reshape(2,3)
i = nditer(a, op_flags=['readwrite'])
for x in i:
assert type(x) is ndarray
assert x.base is i
assert x.shape == ()
assert x.strides == ()
x[...] = 2 * x
assert (a == [[0, 2, 4], [6, 8, 10]]).all()
def test_external_loop(self):
from numpy import arange, nditer, array
a = arange(24).reshape(2, 3, 4)
import sys
r = []
for x in nditer(a, flags=['external_loop']):
r.append(x)
assert len(r) == 1
assert r[0].shape == (24,)
assert (array(r) == range(24)).all()
r = []
for x in nditer(a, flags=['external_loop'], order='F'):
r.append(x)
assert len(r) == 12
assert (array(r) == [[ 0, 12], [ 4, 16], [ 8, 20], [ 1, 13], [ 5, 17], [ 9, 21],
[ 2, 14], [ 6, 18], [10, 22], [ 3, 15], [ 7, 19], [11, 23],
]).all()
e = raises(ValueError, 'r[0][0] = 0')
assert str(e.value) == 'assignment destination is read-only'
r = []
for x in nditer(a.T, flags=['external_loop'], order='F'):
r.append(x)
array_r = array(r)
assert len(array_r.shape) == 2
assert array_r.shape == (1,24)
assert (array(r) == arange(24)).all()
def test_index(self):
from numpy import arange, nditer
a = arange(6).reshape(2,3)
r = []
it = nditer(a, flags=['c_index'])
assert it.has_index
for value in it:
r.append((value, it.index))
assert r == [(0, 0), (1, 1), (2, 2), (3, 3), (4, 4), (5, 5)]
exc = None
try:
it.index
except ValueError as e:
exc = e
assert exc
r = []
it = nditer(a, flags=['f_index'])
assert it.has_index
for value in it:
r.append((value, it.index))
assert r == [(0, 0), (1, 2), (2, 4), (3, 1), (4, 3), (5, 5)]
def test_iters_with_different_order(self):
from numpy import nditer, array
a = array([[1, 2], [3, 4]], order="C")
b = array([[1, 2], [3, 4]], order="F")
it = nditer([a, b])
r = list(it)
assert r == zip(range(1, 5), range(1, 5))
def test_interface(self):
from numpy import arange, nditer, zeros
import sys
a = arange(6).reshape(2,3)
r = []
it = nditer(a, flags=['f_index'])
while not it.finished:
r.append((it[0], it.index))
it.iternext()
assert r == [(0, 0), (1, 2), (2, 4), (3, 1), (4, 3), (5, 5)]
it = nditer(a, flags=['multi_index'], op_flags=['writeonly'])
if '__pypy__' in sys.builtin_module_names:
raises(NotImplementedError, 'it[0] = 3')
skip('nditer.__setitem__ not implmented')
while not it.finished:
it[0] = it.multi_index[1] - it.multi_index[0]
it.iternext()
assert (a == [[0, 1, 2], [-1, 0, 1]]).all()
# b = zeros((2, 3))
# exc = raises(ValueError, nditer, b, flags=['c_index', 'external_loop'])
# assert str(exc.value).startswith("Iterator flag EXTERNAL_LOOP cannot")
def test_buffered(self):
from numpy import arange, nditer, array, isscalar
a = arange(24).reshape(2, 3, 4)
r = []
for x in nditer(a, flags=['external_loop'], order='F'):
r.append(x)
array_r = array(r)
assert len(array_r.shape) == 2
assert array_r.shape == (12, 2)
assert (array_r == [[0, 12], [4, 16], [8, 20], [1, 13], [5, 17], [9, 21],
[2, 14], [6, 18], [10, 22], [3, 15], [7, 19], [11, 23]]).all
assert (a == arange(24).reshape(2, 3, 4)).all()
a[0,0,0] = 100
assert r[0][0] == 100
r = []
it = nditer(a, flags=['buffered'], order='F')
for x in it:
r.append(x)
array_r = array(r)
assert len(array_r.shape) == 1
assert array_r.shape == (24,)
assert r[0].shape == ()
assert not isscalar(r[0])
assert (array_r == [0, 12, 4, 16, 8, 20, 1, 13, 5, 17, 9, 21,
2, 14, 6, 18, 10, 22, 3, 15, 7, 19, 11, 23]).all
assert a.shape == (2, 3, 4)
a[0,0,0] = 0
# buffered copies the data into a tmp array
assert r[0] == 100
assert (a == arange(24).reshape(2, 3, 4)).all()
r = []
for x in nditer(a, flags=['external_loop', 'buffered'], order='F'):
r.append(x)
assert r[0].shape == (24,)
assert (array_r == [0, 12, 4, 16, 8, 20, 1, 13, 5, 17, 9, 21,
2, 14, 6, 18, 10, 22, 3, 15, 7, 19, 11, 23]).all
assert a.shape == (2, 3, 4)
assert (a == arange(24).reshape(2, 3, 4)).all()
def test_zerosize(self):
from numpy import nditer, array
for a in [ array([]), array([1]), array([1, 2]) ]:
buffersize = max(16 * 1024 ** 2 // a.itemsize, 1)
r = []
for chunk in nditer(a,
flags=['external_loop', 'buffered', 'zerosize_ok'],
buffersize=buffersize, order='C'):
r.append(chunk)
assert (r == a).all()
def test_op_dtype(self):
from numpy import arange, nditer, sqrt, array
a = arange(6).reshape(2,3) - 3
exc = raises(TypeError, nditer, a, op_dtypes=['complex'])
assert str(exc.value).startswith("Iterator operand required copying or buffering")
exc = raises(ValueError, nditer, a, op_flags=['copy'], op_dtypes=['complex128'])
assert str(exc.value) == "None of the iterator flags READWRITE," \
" READONLY, or WRITEONLY were specified for an operand"
r = []
for x in nditer(a, op_flags=['readonly','copy'],
op_dtypes=['complex128']):
r.append(sqrt(x))
assert abs((array(r) - [1.73205080757j, 1.41421356237j, 1j, 0j,
1+0j, 1.41421356237+0j]).sum()) < 1e-5
multi = nditer([None, array([2, 3], dtype='int64'), array(2., dtype='double')],
op_dtypes=['int64', 'int64', 'float64'],
op_flags=[['writeonly', 'allocate'], ['readonly'], ['readonly']])
for a, b, c in multi:
a[...] = b * c
assert (multi.operands[0] == [4, 6]).all()
def test_casting(self):
from numpy import arange, nditer
import sys
a = arange(6.)
exc = raises(TypeError, nditer, a, flags=['buffered'], op_dtypes=['float32'])
assert str(exc.value) == "Iterator operand 0 dtype could not be " + \
"cast from dtype('float64') to dtype('float32') according to the" +\
" rule 'safe'"
r = []
for x in nditer(a, flags=['buffered'], op_dtypes=['float32'],
casting='same_kind'):
r.append(x)
assert r == [0., 1., 2., 3., 4., 5.]
exc = raises(TypeError, nditer, a, flags=['buffered'],
op_dtypes=['int32'], casting='same_kind')
assert str(exc.value).startswith("Iterator operand 0 dtype could not be cast")
r = []
b = arange(6)
exc = raises(TypeError, nditer, b, flags=['buffered'], op_dtypes=['float64'],
op_flags=['readwrite'], casting='same_kind')
assert str(exc.value).startswith("Iterator requested dtype could not be cast")
def test_broadcast(self):
from numpy import arange, nditer
a = arange(3)
b = arange(6).reshape(2,3)
r = []
it = nditer([a, b])
assert it.itersize == 6
for x,y in it:
r.append((x, y))
assert r == [(0, 0), (1, 1), (2, 2), (0, 3), (1, 4), (2, 5)]
a = arange(2)
exc = raises(ValueError, nditer, [a, b])
assert str(exc.value).find('shapes (2,) (2,3)') > 0
def test_outarg(self):
from numpy import nditer, zeros, arange
import sys
def square1(a):
it = nditer([a, None])
for x,y in it:
y[...] = x*x
return it.operands[1]
assert (square1([1, 2, 3]) == [1, 4, 9]).all()
def square2(a, out=None):
it = nditer([a, out], flags=['external_loop', 'buffered'],
op_flags=[['readonly'],
['writeonly', 'allocate', 'no_broadcast']])
for x,y in it:
y[...] = x*x
return it.operands[1]
assert (square2([1, 2, 3]) == [1, 4, 9]).all()
b = zeros((3, ))
c = square2([1, 2, 3], out=b)
assert (c == [1., 4., 9.]).all()
assert (b == c).all()
exc = raises(ValueError, square2, arange(6).reshape(2, 3), out=b)
assert str(exc.value).find("doesn't match the broadcast shape") > 0
def test_outer_product(self):
from numpy import nditer, arange
a = arange(3)
import sys
b = arange(8).reshape(2,4)
if '__pypy__' in sys.builtin_module_names:
raises(NotImplementedError, nditer, [a, b, None], flags=['external_loop'],
op_axes=[[0, -1, -1], [-1, 0, 1], None])
skip('nditer op_axes not implemented yet')
it = nditer([a, b, None], flags=['external_loop'],
op_axes=[[0, -1, -1], [-1, 0, 1], None])
for x, y, z in it:
z[...] = x*y
assert it.operands[2].shape == (3, 2, 4)
for i in range(a.size):
assert (it.operands[2][i] == a[i]*b).all()
def test_reduction(self):
from numpy import nditer, arange, array
import sys
a = arange(24).reshape(2, 3, 4)
b = array(0)
if '__pypy__' in sys.builtin_module_names:
raises(NotImplementedError, nditer, [a, b], flags=['reduce_ok'])
skip('nditer reduce_ok not implemented yet')
#reduction operands must be readwrite
for x, y in nditer([a, b], flags=['reduce_ok', 'external_loop'],
op_flags=[['readonly'], ['readwrite']]):
y[...] += x
assert b == 276
assert b == a.sum()
# reduction and allocation requires op_axes and initialization
it = nditer([a, None], flags=['reduce_ok', 'external_loop'],
op_flags=[['readonly'], ['readwrite', 'allocate']],
op_axes=[None, [0,1,-1]])
it.operands[1][...] = 0
for x, y in it:
y[...] += x
assert (it.operands[1] == [[6, 22, 38], [54, 70, 86]]).all()
assert (it.operands[1] == a.sum(axis=2)).all()
# previous example with buffering, requires more flags and reset
it = nditer([a, None], flags=['reduce_ok', 'external_loop',
'buffered', 'delay_bufalloc'],
op_flags=[['readonly'], ['readwrite', 'allocate']],
op_axes=[None, [0,1,-1]])
it.operands[1][...] = 0
it.reset()
for x, y in it:
y[...] += x
assert (it.operands[1] == [[6, 22, 38], [54, 70, 86]]).all()
assert (it.operands[1] == a.sum(axis=2)).all()
def test_get_dtypes(self):
from numpy import array, nditer
x = array([1, 2])
y = array([1.0, 2.0])
assert nditer([x, y]).dtypes == (x.dtype, y.dtype)
def test_multi_index(self):
import numpy as np
a = np.arange(6).reshape(2, 3)
it = np.nditer(a, flags=['multi_index'])
res = []
while not it.finished:
res.append((it[0], it.multi_index))
it.iternext()
assert res == [(0, (0, 0)), (1, (0, 1)),
(2, (0, 2)), (3, (1, 0)),
(4, (1, 1)), (5, (1, 2))]
def test_itershape(self):
# Check that allocated outputs work with a specified shape
from numpy import nditer, arange
import sys
if '__pypy__' in sys.builtin_module_names:
skip("op_axes not totally supported yet")
a = arange(6, dtype='i2').reshape(2,3)
i = nditer([a, None], [], [['readonly'], ['writeonly','allocate']],
op_axes=[[0,1,None], None],
itershape=(-1,-1,4))
assert i.operands[1].shape == (2,3,4)
assert i.operands[1].strides, (24,8,2)
i = nditer([a.T, None], [], [['readonly'], ['writeonly','allocate']],
op_axes=[[0,1,None], None],
itershape=(-1,-1,4))
assert i.operands[1].shape, (3,2,4)
assert i.operands[1].strides, (8,24,2)
i = nditer([a.T, None], [], [['readonly'], ['writeonly','allocate']],
order='F',
op_axes=[[0,1,None], None],
itershape=(-1,-1,4))
assert i.operands[1].shape, (3,2,4)
assert i.operands[1].strides, (2,6,12)
# If we specify 1 in the itershape, it shouldn't allow broadcasting
# of that dimension to a bigger value
raises(ValueError, nditer, [a, None], [],
[['readonly'], ['writeonly','allocate']],
op_axes=[[0,1,None], None],
itershape=(-1,1,4))
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