Guide to Reading the API Reference
The API documentation is auto-generated using sphinx and the napolean sphinx extension. Some of the layout and terminology may need some more explanation.
The documentation is now built with intersphinx which makes references to types from the Python standard library and most external packages clickable. So, for example, if you see a function with a type pd.DataFrame you can click on that and you will be taken to pandas documentation for the pandas DataFrame.
API Documentation Structure
The API listings are grouped by sub-package, then module, then class.
The class layout can appear a little confusing because of some limitations of the auto-documentation (or more likely some limitations of my knowledge of how to use it).
In particular, the documented public attributes of classes (actually, attributes of class instances) are included without a header section.
Class documentation is layed out in the following structure:
- Class summary: the
__init__
signature header - Attributes:
Documented public attributes (other than explicit properties). The Attributes section has no title so everything you see until the instance creation documentation is an attribute.
- Class instantiation:
the
__init__
signature and documentation, i.e. the syntax to create a new instance of this class.
Class methods and Class properties.
- Class summary: the
Type Annotations
The package uses type annotations with types imported from the
typing
library. For a full explanation of how these are used
and how to interpret some of the odder-looking types please
see PEP 484.
typing
uses abstract classes to help deal with duck typing - e.g.
MyFancyList
may implement all required list
interfaces but not
actually be derived from list
.
Most of the types used are easily interpretable (e.g. Tuple ~= tuple
)
with the advantage that you can supply type annotations to Tuple’s
members - e.g. Tuple[str, int, float]
.
For all type annotations used from the Python typing
module,
you can click on the type in the API documentation to navigate
to the Python docs official documentation.
Some members of typing
commonly used in are a little more esoteric
than List
or Tuple
:
Mapping
An object supporting keyed access to its members (like a dict
).
E.g. Mapping[str, MyClass]
: when this appears in a parameter type
annotation, it means that any dict-like object (that takes a type str
as a key and returns an object of type MyClass) T2 is acceptable.
This is more rarely used in return type annotations but means that
the returned object will support keyed access to members but not necessarily
implement everything that dict
supports.
Iterable
An object that supports iterator interface.
e.g. Iterable[int]
Optional
The specified type maybe present or None.
e.g. Optional[str]
: means that either str or None is
accepted or returned.
Union
More general form of Optional
where multiple types are
acceptable.
e.g. Union[str, float]
: means that either a str or a float is acceptable
Any
Any type is acceptable.