# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1244585161 -7200
# Node ID 427c42d0e3c891eb5653de47041643a042dbf6e5
# Parent  d78039f0071a51128139ae2c2a2f0fba515069a9
Added new example.

diff -r d78039f0071a -r 427c42d0e3c8 examples/simple_continuous_queue.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/simple_continuous_queue.py	Wed Jun 10 00:06:01 2009 +0200
@@ -0,0 +1,71 @@
+#!/usr/bin/env python
+
+"""
+A simple example of parallel computation using a queue and continuous
+communications.
+"""
+
+import pprocess
+import time
+#import random
+
+# Array size and a limit on the number of processes.
+
+N = 10
+limit = 10
+delay = 1
+
+# Work function.
+
+def calculate(ch, i):
+
+    """
+    A supposedly time-consuming calculation on 'i'.
+    """
+
+    for j in range(0, N):
+        #time.sleep(delay * random.random())
+        time.sleep(delay)
+        ch.send((i, j, i * N + j))
+
+# Main program.
+
+if __name__ == "__main__":
+
+    t = time.time()
+
+    # Initialise the communications queue with a limit on the number of
+    # channels/processes.
+
+    queue = pprocess.Queue(limit=limit, continuous=1)
+
+    # Initialise an array.
+
+    results = [0] * N * N
+
+    # Manage the calculate function.
+
+    calc = queue.manage(calculate)
+
+    # Perform the work.
+
+    print "Calculating..."
+    for i in range(0, N):
+        calc(i)
+
+    # Store the results as they arrive.
+
+    print "Finishing..."
+    for i, j, result in queue:
+        results[i*N+j] = result
+
+    # Show the results.
+
+    for i in range(0, N):
+        for result in results[i*N:i*N+N]:
+            print result,
+        print
+
+    print "Time taken:", time.time() - t
+
+# vim: tabstop=4 expandtab shiftwidth=4