iode.Scalars.__getitem__

Scalars.__getitem__(key: str | List[str]) → Scalar | Self[source]

Return the (subset of) scalar(s) referenced by key.

The key can represent a single object name (e.g. “ACAF”) or a list of object names (“ACAF;ACAG;AOUC”) or a pattern (e.g. “A*”) or a list of sub-patterns (e.g. “A*;*_”).

If the key represents a list of object names or of sub-patterns, each name or sub-pattern is separated by a separator character which is either a whitespace ` , or a comma `,, or a semi-colon ;, or a tabulation t, or a newline n.

A (sub-)`pattern` is a list of characters representing a group of object names. It includes some special characters which have a special meaning:

  • * : any character sequence, even empty

  • ? : any character (one and only one)

  • @ : any alphanumerical char [A-Za-z0-9]

  • & : any non alphanumerical char

  • | : any alphanumeric character or none at the beginning and end of a string

  • ! : any non-alphanumeric character or none at the beginning and end of a string

  • `` : escape the next character

Note that the key can contain references to IODE lists which are prefixed with the symbol $.

Parameters:
key: str or list(str)

(the list of) name(s) of the scalar(s) to get. The list of scalars to get can be specified by a pattern or by a list of sub-patterns (e.g. “A*;*_”).

Returns:
Single scalar or a subset of the database.

Examples

>>> from iode import SAMPLE_DATA_DIR
>>> from iode import scalars
>>> scalars.load(f"{SAMPLE_DATA_DIR}/fun.scl")
Loading .../fun.scl
161 objects loaded 

>>> # a) get one scalar
>>> acaf1 = scalars["acaf1"]
>>> acaf1
Scalar(0.0157684, 1, 0.00136871)
>>> acaf1.value
0.01576840691268444
>>> acaf1.relax
1.0
>>> acaf1.std
0.0013687137980014086

>>> # b) get a subset of the Scalars database using a pattern
>>> scalars_subset = scalars["a*"]
>>> scalars_subset.names
['acaf1', 'acaf2', 'acaf3', 'acaf4']

>>> # c) get a subset of the Scalars database using a list of names
>>> scalars_subset = scalars[["acaf1", "acaf4", "dpuh_1", "dpuh_2"]]
>>> scalars_subset.names
['acaf1', 'acaf4', 'dpuh_1', 'dpuh_2']