class mlpy.auxiliary.datastructs.PriorityQueue(func=<function <lambda>>)[source]

Bases: mlpy.auxiliary.datastructs.Queue

The priority queue.

In a priority queue each element has a priority associated with it. An element with high priority (i.e., smallest value) is served before an element with low priority (i.e., largest value). The priority queue is implemented with a heap.


func : callable

A callback function handling the priority. By default the priority is the value of the element.

See also



>>> q = PriorityQueue()
>>> q.push(5)
>>> q.extend([1, 3, 7])
>>> print q
[(1,1), (5,5), (3,3), (7,7)]

Retrieving the element with highest priority:

>>> q.pop()

Removing an element:

>>> q.remove((3, 3))
>>> print q
[(5,5), (7,7)]

Get the element in the queue identical to the given item:

>>> q.get(7)

Check if the queue is empty:

>>> q.empty()

Loop over the elements in the queue:

>>> for x in q:
>>>     print x
(5, 5)
(7, 7)

Check if an element is in the queue:

>>> if 7 in q:
>>>     print "yes"


empty() Check if the queue is empty.
extend(items) Extend the queue by a number of elements.
get(item) Return the element in the queue identical to item.
pop() Get the element with the highest priority.
push(item) Push an element on the priority queue.
remove(item) Remove an element from the queue.