caterva2.get_chunk#

caterva2.get_chunk(path, nchunk, urlbase=None, auth_cookie=None)#

Retrieves a specified compressed chunk from a dataset.

Parameters:

path¶ (str) – Path of the dataset.
nchunk¶ (int) – ID of the unidimensional chunk to retrieve.
urlbase¶ (str, optional) – Base URL to query. Default to caterva2.sub_urlbase_default.
auth_cookie¶ (str, optional) – HTTP cookie for authorization.

Returns:

The compressed chunk data.

Return type:

bytes obj

Examples

>>> import caterva2 as cat2
>>> urlbase = 'https://demo.caterva2.net'
>>> cat2.subscribe('example', urlbase)
'Ok'
>>> info_schunk = cat2.get_info('example/ds-2d-fields.b2nd', urlbase)['schunk']
>>> info_schunk['nchunks']
1
>>> info_schunk['cratio']
6.453000645300064
>>> chunk = cat2.get_chunk('example/ds-2d-fields.b2nd', 0,  urlbase)
>>> info_schunk['chunksize'] / len(chunk)
6.453000645300064