summaryrefslogtreecommitdiffstats
path: root/third_party/bintrees/README.txt
blob: ba8136055d45bd0c05682960327f7e8169d12618 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
Binary Tree Package
===================

Abstract
========

This package provides Binary- RedBlack- and AVL-Trees written in Python and Cython.

This Classes are much slower than the built-in dict class, but all
iterators/generators yielding data in sorted key order.

Source of Algorithms
--------------------

AVL- and RBTree algorithms taken from Julienne Walker: http://eternallyconfuzzled.com/jsw_home.aspx

Trees written in Python (only standard library)
-----------------------------------------------

    - *BinaryTree* -- unbalanced binary tree
    - *AVLTree* -- balanced AVL-Tree
    - *RBTree* -- balanced Red-Black-Tree

Trees written with C-Functions and Cython as wrapper
----------------------------------------------------

    - *FastBinaryTree* -- unbalanced binary tree
    - *FastAVLTree* -- balanced AVL-Tree
    - *FastRBTree* -- balanced Red-Black-Tree

All trees provides the same API, the pickle protocol is supported.

FastXTrees has C-structs as tree-node structure and C-implementation for low level
operations: insert, remove, get_value, max_item, min_item.

Constructor
~~~~~~~~~~~

    * Tree() -> new empty tree;
    * Tree(mapping) -> new tree initialized from a mapping (requires only an items() method)
    * Tree(seq) -> new tree initialized from seq [(k1, v1), (k2, v2), ... (kn, vn)]

Methods
~~~~~~~

    * __contains__(k) -> True if T has a key k, else False, O(log(n))
    * __delitem__(y) <==> del T[y], del[s:e], O(log(n))
    * __getitem__(y) <==> T[y], T[s:e], O(log(n))
    * __iter__() <==> iter(T)
    * __len__() <==> len(T), O(1)
    * __max__() <==> max(T), get max item (k,v) of T, O(log(n))
    * __min__() <==> min(T), get min item (k,v) of T, O(log(n))
    * __and__(other) <==> T & other, intersection
    * __or__(other) <==> T | other, union
    * __sub__(other) <==> T - other, difference
    * __xor__(other) <==> T ^ other, symmetric_difference
    * __repr__() <==> repr(T)
    * __setitem__(k, v) <==> T[k] = v, O(log(n))
    * clear() -> None, remove all items from T, O(n)
    * copy() -> a shallow copy of T, O(n*log(n))
    * discard(k) -> None, remove k from T, if k is present, O(log(n))
    * get(k[,d]) -> T[k] if k in T, else d, O(log(n))
    * is_empty() -> True if len(T) == 0, O(1)
    * items([reverse]) -> generator for (k, v) items of T, O(n)
    * keys([reverse]) -> generator for keys of T, O(n)
    * values([reverse]) -> generator for values of  T, O(n)
    * pop(k[,d]) -> v, remove specified key and return the corresponding value, O(log(n))
    * popitem() -> (k, v), remove and return some (key, value) pair as a 2-tuple, O(log(n))
    * setdefault(k[,d]) -> T.get(k, d), also set T[k]=d if k not in T, O(log(n))
    * update(E) -> None.  Update T from dict/iterable E, O(E*log(n))
    * foreach(f, [order]) -> visit all nodes of tree (0 = 'inorder', -1 = 'preorder' or +1 = 'postorder') and call f(k, v) for each node, O(n)

slicing by keys
~~~~~~~~~~~~~~~

    * itemslice(s, e) -> generator for (k, v) items of T for s <= key < e, O(n)
    * keyslice(s, e) -> generator for keys of T for s <= key < e, O(n)
    * valueslice(s, e) -> generator for values of T for s <= key < e, O(n)
    * T[s:e] -> TreeSlice object, with keys in range s <= key < e, O(n)
    * del T[s:e] -> remove items by key slicing, for s <= key < e, O(n)

    start/end parameter:

    * if 's' is None or T[:e] TreeSlice/iterator starts with value of min_key();
    * if 'e' is None or T[s:] TreeSlice/iterator ends with value of max_key();
    * T[:] is a TreeSlice which represents the whole tree;

    TreeSlice is a tree wrapper with range check, and contains no references
    to objects, deleting objects in the associated tree also deletes the object
    in the TreeSlice.

    * TreeSlice[k] -> get value for key k, raises KeyError if k not exists in range s:e
    * TreeSlice[s1:e1] -> TreeSlice object, with keys in range s1 <= key < e1
        - new lower bound is max(s, s1)
        - new upper bound is min(e, e1)

    TreeSlice methods:

    * items() -> generator for (k, v) items of T, O(n)
    * keys() -> generator for keys of T, O(n)
    * values() -> generator for values of  T, O(n)
    * __iter__ <==> keys()
    * __repr__ <==> repr(T)
    * __contains__(key)-> True if TreeSlice has a key k, else False, O(log(n))

prev/succ operations
~~~~~~~~~~~~~~~~~~~~

    * prev_item(key) -> get (k, v) pair, where k is predecessor to key, O(log(n))
    * prev_key(key) -> k, get the predecessor of key, O(log(n))
    * succ_item(key) -> get (k,v) pair as a 2-tuple, where k is successor to key, O(log(n))
    * succ_key(key) -> k, get the successor of key, O(log(n))
    * floor_item(key) -> get (k, v) pair, where k is the greatest key less than or equal to key, O(log(n))
    * floor_key(key) -> k, get the greatest key less than or equal to key, O(log(n))
    * ceiling_item(key) -> get (k, v) pair, where k is the smallest key greater than or equal to key, O(log(n))
    * ceiling_key(key) -> k, get the smallest key greater than or equal to key, O(log(n))

Heap methods
~~~~~~~~~~~~

    * max_item() -> get largest (key, value) pair of T, O(log(n))
    * max_key() -> get largest key of T, O(log(n))
    * min_item() -> get smallest (key, value) pair of T, O(log(n))
    * min_key() -> get smallest key of T, O(log(n))
    * pop_min() -> (k, v), remove item with minimum key, O(log(n))
    * pop_max() -> (k, v), remove item with maximum key, O(log(n))
    * nlargest(i[,pop]) -> get list of i largest items (k, v), O(i*log(n))
    * nsmallest(i[,pop]) -> get list of i smallest items (k, v), O(i*log(n))

Set methods (using frozenset)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    * intersection(t1, t2, ...) -> Tree with keys *common* to all trees
    * union(t1, t2, ...) -> Tree with keys from *either* trees
    * difference(t1, t2, ...) -> Tree with keys in T but not any of t1, t2, ...
    * symmetric_difference(t1) -> Tree with keys in either T and t1  but not both
    * issubset(S) -> True if every element in T is in S
    * issuperset(S) -> True if every element in S is in T
    * isdisjoint(S) ->  True if T has a null intersection with S

Classmethods
~~~~~~~~~~~~

    * fromkeys(S[,v]) -> New tree with keys from S and values equal to v.

Performance
===========

Profiling with timeit(): 5000 unique random int keys, time in seconds

========================  =============  ==============  ==============  ==============
unbalanced Trees          CPython 2.7.2  FastBinaryTree  ipy 2.7.0       pypy 1.7.0
========================  =============  ==============  ==============  ==============
build time 100x            7,55           0,60            2,51            0,29
build & delete time 100x  13,34           1,48            4,45            0,47
search 100x all keys       2,86           0,96            0,27            0,06
========================  =============  ==============  ==============  ==============

========================  =============  ==============  ==============  ==============
AVLTrees                  CPython 2.7.2  FastAVLTree     ipy 2.7.0       pypy 1.7.0
========================  =============  ==============  ==============  ==============
build time 100x	          22,66           0,65           10,45            1,29
build & delete time 100x  36,71           1,47           20,89            3,02
search 100x all keys       2,34           0,85            0,89            0,14
========================  =============  ==============  ==============  ==============

========================  =============  ==============  ==============  ==============
RBTrees                   CPython 2.7.2  FastRBTree      ipy 2.7.0       pypy 1.7.0
========================  =============  ==============  ==============  ==============
build time 100x	          14,78           0,65            4,43            0,49
build & delete time 100x  39,34           1,63           12,43            1,32
search 100x all keys       2,32           0,86            0,86            0,13
========================  =============  ==============  ==============  ==============

News
====

Version 1.0.1 February 2013

  * bug fixes
  * refactorings by graingert
  * skip useless tests for pypy
  * new license: MIT License
  * tested with CPython2.7, CPython3.2, CPython3.3, pypy-1.9, pypy-2.0-beta1
  * unified line endings to LF
  * PEP8 refactorings
  * added floor_item/key, ceiling_item/key methods, thanks to Dai Mikurube

Version 1.0.0

  * bug fixes
  * status: 5 - Production/Stable
  * removed useless TreeIterator() class and T.treeiter() method.
  * patch from Max Motovilov to use Visual Studio 2008 for building C-extensions

Version 0.4.0

  * API change!!!
  * full Python 3 support, also for Cython implementations
  * removed user defined compare() function - keys have to be comparable!
  * removed T.has_key(), use 'key in T'
  * keys(), items(), values() generating 'views'
  * removed iterkeys(), itervalues(), iteritems() methods
  * replaced index slicing by key slicing
  * removed index() and item_at()
  * repr() produces a correct representation
  * installs on systems without cython (tested with pypy)
  * new license: GNU Library or Lesser General Public License (LGPL)

Installation
============

from source::

    python setup.py install

Download
========

http://bitbucket.org/mozman/bintrees/downloads

Documentation
=============

this README.txt

bintrees can be found on bitbucket.org at:

http://bitbucket.org/mozman/bintrees