caterva2.Client.lazyexpr

Client.lazyexpr(name, expression, operands=None, compute=False)

Creates a lazy expression dataset in personal space.

A dataset with the specified name will be created or overwritten if already exists.

Parameters:

• name (str) – Name of the dataset to be created (without extension).

• expression (str) – Expression to be evaluated, which must yield a lazy expression.

• operands (dict) – Mapping of variables in the expression to their corresponding dataset paths.

• compute (bool, optional) – If false, generate lazyexpr and do not compute anything. If true, compute lazy expression on creation and save (full) result. Default false.

Returns:

Path of the created dataset.

Return type:

Path

Examples

>>> import caterva2 as cat2
>>> import numpy as np
>>> # To create a lazyexpr you need to be a registered used
>>> client = cat2.Client('https://cat2.cloud/demo', ("joedoe@example.com", "foobar"))
>>> src_path = f'@personal/dir{np.random.randint(0, 100)}/ds-4d.b2nd'
>>> path = client.upload('root-example/dir1/ds-2d.b2nd', src_path)
>>> client.lazyexpr('example-expr', 'a + a', {'a': path})
PurePosixPath('@personal/example-expr.b2nd')
>>> 'example-expr.b2nd' in client.get_list('@personal')
True