31. collection — Tools for handling collections of elements belonging to multiple parts.

This module defines the Collection class.

class collection.Collection(object_type=None)

A collection is a set of (int,int) tuples.

The first part of the tuple has a limited number of values and are used as the keys in a dict. The second part can have a lot of different values and is implemented as an integer array with unique values. This is e.g. used to identify a set of individual parts of one or more OpenGL actors.

Examples:

>>> a = Collection()
>>> a.add(range(7),3)
>>> a.add(range(4))
>>> a.remove([2,4],3)
>>> print(a)
-1 [0 1 2 3]; 3 [0 1 3 5 6];
>>> a.add([[2,0],[2,3],[-1,7],[3,88]])
>>> print(a)
-1 [0 1 2 3 7]; 2 [0 3]; 3 [ 0  1  3  5  6 88];
>>> a[2] = [1,2,3]
>>> print(a)
-1 [0 1 2 3 7]; 2 [1 2 3]; 3 [ 0  1  3  5  6 88];
>>> a[2] = []
>>> print(a)
-1 [0 1 2 3 7]; 3 [ 0  1  3  5  6 88];
>>> a.set([[2,0],[2,3],[-1,7],[3,88]])
>>> print(a)
-1 [7]; 2 [0 3]; 3 [88];
>>> print(a.keys())
[-1  2  3]
>>> print([k for k in a])
[-1, 2, 3]
>>> 2 in a
True

add(data, key=-1)

Add new data to the collection.

data can be a 2d array with (key,val) tuples or a 1-d array of values. In the latter case, the key has to be specified separately, or a default value will be used.

data can also be another Collection, if it has the same object type.

set(data, key=-1)

Set the collection to the specified data.

This is equivalent to clearing the corresponding keys before adding.

remove(data, key=-1)

Remove data from the collection.

get(key, default=[])

Return item with given key or default.

keys()

Return a sorted array with the keys

items()

Return an iterator over (key,value) pairs.