def _g_create(self):
"""Save a new array in file."""
self._v_version = obversion
try:
# `Leaf._g_postInitHook()` should be setting the flavor on disk.
self._flavor = flavor = flavor_of(self._object)
nparr = array_as_internal(self._object, flavor)
except: #XXX
# Problems converting data. Close the node and re-raise exception.
self.close(flush=0)
raise
# Raise an error in case of unsupported object
if nparr.dtype.kind in ['V', 'U', 'O']: # in void, unicode, object
raise TypeError, \
"Array objects cannot currently deal with void, unicode or object arrays"
# Decrease the number of references to the object
self._object = None
# The shape of this array
self.shape = tuple(SizeType(s) for s in nparr.shape)
# Fix the byteorder of data
nparr = self._g_fix_byteorder_data(nparr, nparr.dtype.byteorder)
# Create the array on-disk
try:
# ``self._v_objectID`` needs to be set because would be
# needed for setting attributes in some descendants later
# on
(self._v_objectID, self.atom) = self._createArray(
nparr, self._v_new_title)
except: #XXX
# Problems creating the Array on disk. Close node and re-raise.
self.close(flush=0)
raise
# Compute the optimal buffer size
chunkshape = self._calc_chunkshape(
self.nrows, self.rowsize, self.atom.itemsize)
self.nrowsinbuf = self._calc_nrowsinbuf(
chunkshape, self.rowsize, self.atom.itemsize)
# Arrays don't have chunkshapes (so, set it to None)
self._v_chunkshape = None
return self._v_objectID
def _g_create(self):
"""Save a new array in file."""
self._v_version = obversion
try:
# `Leaf._g_postInitHook()` should be setting the flavor on disk.
self._flavor = flavor = flavor_of(self._object)
nparr = array_as_internal(self._object, flavor)
except: #XXX
# Problems converting data. Close the node and re-raise exception.
self.close(flush=0)
raise
# Raise an error in case of unsupported object
if nparr.dtype.kind in ['V', 'U', 'O']: # in void, unicode, object
raise TypeError, \
"Array objects cannot currently deal with void, unicode or object arrays"
# Decrease the number of references to the object
self._object = None
# The shape of this array
self.shape = tuple(SizeType(s) for s in nparr.shape)
# Fix the byteorder of data
nparr = self._g_fix_byteorder_data(nparr, nparr.dtype.byteorder)
# Create the array on-disk
try:
# ``self._v_objectID`` needs to be set because would be
# needed for setting attributes in some descendants later
# on
(self._v_objectID,
self.atom) = self._createArray(nparr, self._v_new_title)
except: #XXX
# Problems creating the Array on disk. Close node and re-raise.
self.close(flush=0)
raise
# Compute the optimal buffer size
chunkshape = self._calc_chunkshape(self.nrows, self.rowsize,
self.atom.itemsize)
self.nrowsinbuf = self._calc_nrowsinbuf(chunkshape, self.rowsize,
self.atom.itemsize)
# Arrays don't have chunkshapes (so, set it to None)
self._v_chunkshape = None
return self._v_objectID
def create_earray(fileobj,
where,
name,
atom=None,
shape=None,
title="",
filters=None,
expectedrows=1000,
chunkshape=None,
byteorder=None,
createparents=False,
obj=None):
"""Create a new enlargeable array.
Parameters
----------
fileobj: File instance
file in which creating the table
where : str or Group
The parent group from which the new array will hang. It can be a
path string (for example '/level1/leaf5'), or a Group instance
(see :ref:`GroupClassDescr`).
name : str
The name of the new array
atom : Atom
An Atom (see :ref:`AtomClassDescr`) instance representing the
*type* and *shape* of the atomic objects to be saved.
.. versionchanged:: 3.0
The *atom* parameter can be None (default) if *obj* is
provided.
shape : tuple
The shape of the new array. One (and only one) of the shape
dimensions *must* be 0. The dimension being 0 means that the
resulting EArray object can be extended along it. Multiple
enlargeable dimensions are not supported right now.
.. versionchanged:: 3.0
The *shape* parameter can be None (default) if *obj* is
provided.
title : str, optional
A description for this node (it sets the TITLE HDF5 attribute on
disk).
expectedrows : int, optional
A user estimate about the number of row elements that will be added
to the growable dimension in the EArray node. If not provided, the
default value is EXPECTED_ROWS_EARRAY (see tables/parameters.py).
If you plan to create either a much smaller or a much bigger array
try providing a guess; this will optimize the HDF5 B-Tree creation
and management process time and the amount of memory used.
chunkshape : tuple, numeric, or None, optional
The shape of the data chunk to be read or written in a single HDF5
I/O operation. Filters are applied to those chunks of data. The
dimensionality of chunkshape must be the same as that of shape
(beware: no dimension should be 0 this time!). If None, a sensible
value is calculated based on the expectedrows parameter (which is
recommended).
byteorder : str, optional
The byteorder of the data *on disk*, specified as 'little' or
'big'. If this is not specified, the byteorder is that of the
platform.
createparents : bool, optional
Whether to create the needed groups for the parent path to exist
(not done by default).
obj : python object
The array or scalar to be saved. Accepted types are NumPy
arrays and scalars, as well as native Python sequences and
scalars, provided that values are regular (i.e. they are
not like ``[[1,2],2]``) and homogeneous (i.e. all the
elements are of the same type).
The *obj* parameter is optional and it can be provided in
alternative to the *atom* and *shape* parameters.
If both *obj* and *atom* and/or *shape* are provided they must
be consistent with each other.
.. versionadded:: 3.0
See Also
--------
EArray : for more information on enlargeable arrays
"""
if obj is not None:
flavor = flavor_of(obj)
obj = array_as_internal(obj, flavor)
earray_shape = (0, ) + obj.shape[1:]
if shape is not None and shape != earray_shape:
raise TypeError('the shape parameter is not compatible '
'with obj.shape.')
else:
shape = earray_shape
if atom is not None and atom.dtype != obj.dtype:
raise TypeError('the atom parameter is not consistent with '
'the data type of the obj parameter')
elif atom is None:
atom = Atom.from_dtype(obj.dtype)
parentnode = fileobj._getOrCreatePath(where, createparents)
_checkfilters(filters)
ptobj = EArray(parentnode,
name,
atom=atom,
shape=shape,
title=title,
filters=filters,
expectedrows=expectedrows,
chunkshape=chunkshape,
byteorder=byteorder)
if obj is not None:
ptobj.append(obj)
return ptobj