def buffered_ptr(self, idx):
if len(idx) != self.nindex:
raise IndexError('Incorrect number of indices (got %d, require %d)' %
(len(idx), self.nindex))
dst_arr = self.dyndarr[idx]
buf_arr = dst_arr.cast(self._c_dtype).eval()
buf_ptr = _lowlevel.data_address_of(buf_arr)
if buf_ptr == _lowlevel.data_address_of(dst_arr):
# If no buffering is needed, just return the pointer
return buffered_ptr_ctxmgr(buf_ptr, None)
else:
def buffer_flush():
dst_arr[...] = buf_arr
return buffered_ptr_ctxmgr(buf_ptr, buffer_flush)
def __next__(self):
# Copy the previous element to the array if it is buffered
self.flush()
if self._index < self._len:
i = self._index
self._index = i + 1
if self._usebuffer:
if self._buffer is None:
self._buffer = nd.empty(self._c_dtype)
self._buffer_index = i
return _lowlevel.data_address_of(self._buffer)
else:
return _lowlevel.data_address_of(self._dyndarr[i])
else:
raise StopIteration
def test_array_from_ptr(self):
# cfixed_dim arrmeta is redundant so this is ok
a = (ctypes.c_int32 * 3)()
a[0] = 3
a[1] = 6
a[2] = 9
# Readwrite version using cfixed
b = _lowlevel.array_from_ptr('cfixed[3] * int32',
ctypes.addressof(a), a, 'readwrite')
self.assertEqual(_lowlevel.data_address_of(b), ctypes.addressof(a))
self.assertEqual(nd.dshape_of(b), '3 * int32')
self.assertEqual(nd.as_py(b), [3, 6, 9])
b[1] = 10
self.assertEqual(a[1], 10)
# Readonly version using cfixed
b = _lowlevel.array_from_ptr('cfixed[3] * int32',
ctypes.addressof(a), a, 'readonly')
self.assertEqual(nd.as_py(b), [3, 10, 9])
def assign_to(b):
b[1] = 100
self.assertRaises(RuntimeError, assign_to, b)
# Using a fixed dim default-constructs the arrmeta, so works too
b = _lowlevel.array_from_ptr('3 * int32', ctypes.addressof(a),
a, 'readonly')
self.assertEqual(nd.as_py(b), [3, 10, 9])
# Should get an error if we try strided, because the size is unknown
self.assertRaises(RuntimeError,
lambda: _lowlevel.array_from_ptr('strided * int32',
ctypes.addressof(a),
a, 'readonly'))
def read_single(self, idx, count=1):
idxlen = len(idx)
if idxlen != self.nindex:
raise IndexError('Incorrect number of indices (got %d, require %d)' %
(len(idx), self.nindex))
idx = tuple(operator.index(i) for i in idx)
if count == 1:
x = self._dyndarr[idx]
# Make it C-contiguous and in native byte order
x = x.cast(self._c_dtype).eval()
self._tmpbuffer = x
return _lowlevel.data_address_of(x)
else:
idx = idx[:-1] + (slice(idx[-1], idx[-1]+count),)
x = self._dyndarr[idx]
# Make it C-contiguous and in native byte order
x = x.cast(ndt.make_fixed_dim(count, self._c_dtype)).eval()
self._tmpbuffer = x
return _lowlevel.data_address_of(x)
def read_single(self, idx):
if len(idx) != self.nindex:
raise IndexError('Incorrect number of indices (got %d, require %d)' %
(len(idx), self.nindex))
idx = tuple([operator.index(i) for i in idx])
x = self.dyndarr[idx]
# Make it C-contiguous and in native byte order
x = x.cast(self._c_dtype).eval()
self._tmpbuffer = x
return _lowlevel.data_address_of(x)
def __next__(self):
if self._index < self._len:
i = self._index
self._index = i + 1
x = self._dyndarr[i]
# Make it C-contiguous and in native byte order
x = x.cast(self._c_dtype).eval()
self._tmpbuffer = x
return _lowlevel.data_address_of(x)
else:
raise StopIteration
def buffered_ptr(self, idx, count=1):
if len(idx) != self.nindex:
raise IndexError('Incorrect number of indices (got %d, require %d)' %
(len(idx), self.nindex))
idx = tuple(operator.index(i) for i in idx)
c_dtype = self._c_dtype
if count != 1:
idx = idx[:-1] + (slice(idx[-1], idx[-1]+count),)
c_dtype = ndt.make_fixed_dim(count, c_dtype)
dst_arr = self._dyndarr[idx]
buf_arr = dst_arr.cast(c_dtype).eval()
buf_ptr = _lowlevel.data_address_of(buf_arr)
if buf_ptr == _lowlevel.data_address_of(dst_arr):
# If no buffering is needed, just return the pointer
return buffered_ptr_ctxmgr(buf_ptr, None)
else:
def buffer_flush():
dst_arr[...] = buf_arr
return buffered_ptr_ctxmgr(buf_ptr, buffer_flush)
def test_array_from_ptr(self):
a = (ctypes.c_int32 * 3)()
a[0] = 3
a[1] = 6
a[2] = 9
# Readwrite version
b = _lowlevel.array_from_ptr(ndt.type('3 * int32'), ctypes.addressof(a),
a, 'readwrite')
self.assertEqual(_lowlevel.data_address_of(b), ctypes.addressof(a))
self.assertEqual(nd.dshape_of(b), '3 * int32')
self.assertEqual(nd.as_py(b), [3, 6, 9])
b[1] = 10
self.assertEqual(a[1], 10)
# Readonly version
b = _lowlevel.array_from_ptr(ndt.type('3 * int32'), ctypes.addressof(a),
a, 'readonly')
self.assertEqual(nd.as_py(b), [3, 10, 9])
def assign_to(b):
b[1] = 100
self.assertRaises(RuntimeError, assign_to, b)