File: index.html

package info (click to toggle)
python-processing 0.52-1
  • links: PTS, VCS
  • area: main
  • in suites: lenny
  • size: 800 kB
  • ctags: 1,023
  • sloc: python: 5,268; ansic: 1,710; makefile: 58; sh: 54
file content (120 lines) | stat: -rw-r--r-- 5,097 bytes parent folder | download | duplicates (13)
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
<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="generator" content="Docutils 0.4: http://docutils.sourceforge.net/" />
<title>Python processing</title>
<meta name="author" content="R Oudkerk" />
<link rel="stylesheet" href="doc/html4css1.css" type="text/css" />
</head>
<body>
<div class="document" id="python-processing">
<h1 class="title">Python processing</h1>
<table class="docinfo" frame="void" rules="none">
<col class="docinfo-name" />
<col class="docinfo-content" />
<tbody valign="top">
<tr><th class="docinfo-name">Author:</th>
<td>R Oudkerk</td></tr>
<tr><th class="docinfo-name">Contact:</th>
<td>roudkerk at users.berlios.de</td></tr>
<tr class="field"><th class="docinfo-name">Url:</th><td class="field-body"><a class="reference" href="http://developer.berlios.de/projects/pyprocessing">http://developer.berlios.de/projects/pyprocessing</a></td>
</tr>
<tr><th class="docinfo-name">Version:</th>
<td>0.52</td></tr>
<tr class="field"><th class="docinfo-name">Licence:</th><td class="field-body">BSD Licence</td>
</tr>
</tbody>
</table>
<p><tt class="docutils literal"><span class="pre">processing</span></tt> is a package for the Python language which supports the
spawning of processes using the API of the standard library's
<tt class="docutils literal"><span class="pre">threading</span></tt> module.  It runs on both Unix and Windows.</p>
<p>Features:</p>
<ul class="simple">
<li>Objects can be transferred between processes using pipes or
multi-producer/multi-consumer queues.</li>
<li>Objects can be shared between processes using a server process or
(for simple data) shared memory.</li>
<li>Equivalents of all the synchronization primitives in <tt class="docutils literal"><span class="pre">threading</span></tt>
are available.</li>
<li>A <tt class="docutils literal"><span class="pre">Pool</span></tt> class makes it easy to submit tasks to a pool of worker
processes.</li>
</ul>
<div class="section">
<h1><a id="links" name="links">Links</a></h1>
<ul class="simple">
<li><a class="reference" href="./doc/index.html">Documentation</a></li>
<li><a class="reference" href="./doc/INSTALL.html">Installation instructions</a></li>
<li><a class="reference" href="./doc/CHANGES.html">Changelog</a></li>
<li><a class="reference" href="./doc/THANKS.html">Acknowledgments</a></li>
<li><a class="reference" href="./doc/COPYING.html">BSD Licence</a></li>
</ul>
<p>The project is hosted at</p>
<ul class="simple">
<li><a class="reference" href="http://developer.berlios.de/projects/pyprocessing">http://developer.berlios.de/projects/pyprocessing</a></li>
</ul>
<p>The package can be downloaded from</p>
<ul class="simple">
<li><a class="reference" href="http://developer.berlios.de/project/filelist.php?group_id=9001">http://developer.berlios.de/project/filelist.php?group_id=9001</a> or</li>
<li><a class="reference" href="http://pypi.python.org/pypi/processing">http://pypi.python.org/pypi/processing</a></li>
</ul>
</div>
<div class="section">
<h1><a id="examples" name="examples">Examples</a></h1>
<p>The <tt class="docutils literal"><span class="pre">processing.Process</span></tt> class follows the API of <tt class="docutils literal"><span class="pre">threading.Thread</span></tt>.
For example</p>
<pre class="literal-block">
from processing import Process, Queue

def f(q):
    q.put('hello world')

if __name__ == '__main__':
    q = Queue()
    p = Process(target=f, args=[q])
    p.start()
    print q.get()
    p.join()
</pre>
<p>Synchronization primitives like locks, semaphores and conditions are
available, for example</p>
<pre class="literal-block">
&gt;&gt;&gt; from processing import Condition
&gt;&gt;&gt; c = Condition()
&gt;&gt;&gt; print c
&lt;Condition(&lt;RLock(None, 0)&gt;), 0&gt;
&gt;&gt;&gt; c.acquire()
True
&gt;&gt;&gt; print c
&lt;Condition(&lt;RLock(MainProcess, 1)&gt;), 0&gt;
</pre>
<p>One can also use a manager to create shared objects either in shared
memory or in a server process, for example</p>
<pre class="literal-block">
&gt;&gt;&gt; from processing import Manager
&gt;&gt;&gt; manager = Manager()
&gt;&gt;&gt; l = manager.list(range(10))
&gt;&gt;&gt; l.reverse()
&gt;&gt;&gt; print l
[9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
&gt;&gt;&gt; print repr(l)
&lt;Proxy[list] object at 0x00E1B3B0&gt;
</pre>
<p>Tasks can be offloaded to a pool of worker processes in various ways,
for example</p>
<pre class="literal-block">
&gt;&gt;&gt; from processing import Pool
&gt;&gt;&gt; def f(x): return x*x
...
&gt;&gt;&gt; p = Pool(4)
&gt;&gt;&gt; result = p.mapAsync(f, range(10))
&gt;&gt;&gt; print result.get(timeout=1)
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
</pre>
<a href="http://developer.berlios.de" title="BerliOS Developer">
<img src="http://developer.berlios.de/bslogo.php?group_id=9001"
width="124px" height="32px" border="0" alt="BerliOS Developer Logo"></a></div>
</div>
</body>
</html>