# HG changeset patch
# User paulb
# Date 1184540969 0
# Node ID 93872f29ad5147ca6ac77131056f880f13ead03e
# Parent  2b9b685985afaecbe26d1a8266fe78c9383d91df
[project @ 2007-07-15 23:09:29 by paulb]
Extended the example to show managed callables and map-style processing.

diff -r 2b9b685985af -r 93872f29ad51 examples/simple.py
--- a/examples/simple.py	Sun Jul 15 23:09:04 2007 +0000
+++ b/examples/simple.py	Sun Jul 15 23:09:29 2007 +0000
@@ -1,7 +1,9 @@
 #!/usr/bin/env python
 
 """
-A simple example of parallel computation.
+A simple example of parallel computation using message exchanges directly,
+exchanges and managed callables, and map-style processing with parallel-enabled
+functions.
 """
 
 import pprocess
@@ -19,6 +21,8 @@
 
     return [list(x) for x in [(0,) * n] * n]
 
+# Work function and monitoring class.
+
 def calculate(ch, i, j):
 
     """
@@ -37,6 +41,23 @@
         i, j, result = ch.receive()
         self.D[i][j] = result
 
+# Alternative work function.
+
+def calculate_seq(i, j):
+
+    """
+    A version of 'calculate' with a simpler result suitable for sequential
+    collection. It accepts no channel, pretending to be a function used in a
+    non-parallel context.
+    """
+
+    time.sleep(delay)
+    return i * N + j
+
+# The alternative work function converted into a parallel-enabled version.
+
+calculate2 = pprocess.MakeParallel(calculate_seq)
+
 # Main program.
 
 if __name__ == "__main__":
@@ -68,4 +89,39 @@
     for row in exchange.D:
         print row
 
+    # Try again with managed callables.
+
+    exchange.D = make_array(N)
+    calc = exchange.manage(calculate)
+
+    print "Calculating..."
+    for i in range(0, N):
+        for j in range(0, N):
+            calc(i, j)
+            print i, j
+
+    print "Finishing..."
+    exchange.finish()
+
+    print
+    for row in exchange.D:
+        print row
+
+    # Try again with a map, building the results sequentially.
+
+    mymap = pprocess.pmap
+    results = []
+
+    print "Calculating..."
+    for i in range(0, N):
+        sequence = []
+        for j in range(0, N):
+            sequence.append((i, j))
+        results.append(mymap(calculate2, sequence))
+        print i
+
+    print
+    for row in results:
+        print row
+
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