def from_dict(cls, dict_, keys=None, axis=None):
""" Initialize a DimArray for a dictionary of DimArrays
keys, optional: re-order the keys
axis, optional: give a name to the keys axis
"""
assert isinstance(dict_, dict)
from dimarray.dataset import Dataset
if keys is None: keys = dict_.keys()
data = Dataset(dict_)
return data.to_array(axis=axis, keys=keys, _constructor=cls._constructor)
def from_dict(cls, dict_, keys=None, axis=None):
""" Initialize a DimArray for a dictionary of DimArrays
keys, optional: re-order the keys
axis, optional: give a name to the keys axis
"""
assert isinstance(dict_, dict)
from dimarray.dataset import Dataset
if keys is None: keys = dict_.keys()
data = Dataset(dict_)
return data.to_array(axis=axis,
keys=keys,
_constructor=cls._constructor)
def read_dataset(f, nms=None, **kwargs):
""" read several (or all) names from a netCDF file
nms : list of variables to read (default None for all variables)
**kwargs: keyword arguments passed to io.nc.read_variable
"""
kw = _extract_kw(kwargs, ('verbose', ))
f, close = check_file(f, 'r', **kw)
# automatically read all variables to load (except for the dimensions)
if nms is None:
nms, dims = scan(f)
# if nms is str:
# nms = [nms]
data = dict()
for nm in nms:
data[nm] = read_variable(f, nm, **kwargs)
data = Dataset(**data)
# get dataset's metadata
for k in f.ncattrs():
setattr(data, k, f.getncattr(k))
if close: f.close()
return data
def to_dataset(self, axis=0):
""" split a DimArray into a Dataset object (collection of DimArrays)
"""
from dimarray.dataset import Dataset
# iterate over elements of one axis
#data = [val for k, val in self.iter(axis)]
# Dataset(data, keys=self.axes[axis].values)
ds = Dataset()
for k, val in self.iter(axis):
if not isinstance(val, DimArray): # scalar case
val = DimArray(val)
ds[k] = val
return ds
def read(self, names=None, indices=None, axis=0, indexing=None, tol=None, keepdims=False,
verbose=False, # back-compatibility
):
""" Read values from disk
Parameters
----------
names : list of variables to read, optional
indices : int or list or slice (single-dimensional indices)
or a tuple of those (multi-dimensional)
or `dict` of { axis name : axis indices }
Indices refer to Dataset axes. Any item that does not possess
one of the dimensions will not be indexed along that dimension.
For example, scalar items will be left unchanged whatever indices
are provided.
axis : None or int or str, optional
if specified and indices is a slice, scalar or an array, assumes
indexing is along this axis.
indexing : {'label', 'position'}, optional
Indexing mode.
- "label": indexing on axis labels (default)
- "position": use numpy-like position index
Default value can be changed in dimarray.rcParams['indexing.by']
tol : float, optional
tolerance when looking for numerical values, e.g. to use nearest
neighbor search, default `None`.
keepdims : bool, optional
keep singleton dimensions (default False)
Returns
-------
Dataset
See Also
--------
open_nc : examples of use
DimArrayOnDisk.read, DatasetOnDisk.write, DimArray.take
"""
if verbose:
# print "Read ",self.filename
pass
# automatically read all variables to load (except for the dimensions)
if names is None:
dims = self.dims
names = self.keys()
elif isinstance(names, string_types):
return self[names].read(indices=indices, axis=axis, indexing=indexing, tol=tol, keepdims=keepdims)
else:
dims = []
# else:
# raise TypeError("Expected list or str for 'names=', got {}".format(names))
tuple_indices = self._get_indices(indices, axis=axis, tol=tol, keepdims=keepdims, indexing=indexing)
dict_indices = {dim:tuple_indices[i] for i, dim in enumerate(self.dims)}
data = Dataset()
# first load dimensions
for dim in dims:
data.axes.append(self.axes[dim][dict_indices[dim]])
# then normal variables
for nm in names:
data[nm] = self[nm].read(indices={dim:dict_indices[dim] for dim in self[nm].dims}, indexing='position')
data.attrs.update(self.attrs) # dataset's metadata
# reorder the axes in the dataset to match input
data.axes = Axes(data.axes[dim] for dim in self.dims if dim in data.dims)
return data
