3.2 Special Sage Functions

Functions with leading and trailing double underscores __XXX__ are all predefined by Python. Functions with leading and trailing single underscores _XXX_ are defined for Sage. Functions with a single leading underscore are meant to be semi-private, and ones with a double leading underscore are considered really private. Users can create functions with leading and trailing underscores.

Just as Python has many standard special methods for objects, Sage also has special methods. They are typically of the form _XXX_. (In a few cases the trailing underscore is not included, but this will be changed so that the trailing underscore is always included.) This section describes these special methods.

All objects in Sage should derive from the Cython extension class SageObject:

from sage.ext.sage_object import SageObject

class MyClass(SageObject,...):
    ...

or from some other already existing Sage class:

from sage.rings.ring import Algebra

class MyFavoriteAlgebra(Algebra):
    ...

You should implement the _latex_ and _repr_ method for every object. The other methods depend on the nature of the object.

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