1 files changed, 63 insertions, 0 deletions
diff --git a/plac/doc/picalculator.py b/plac/doc/picalculator.py
new file mode 100644
index 0000000..75df2b2
--- /dev/null
+++ b/plac/doc/picalculator.py
@@ -0,0 +1,63 @@
+from __future__ import with_statement
+from random import random
+import multiprocessing
+import plac
+
+class PiCalculator(object):
+    """Compute pi in parallel with threads or processes"""
+    
+    @plac.annotations(
+        npoints=('number of integration points', 'positional', None, int),
+        mode=('sequential|parallel|threaded', 'option', 'm', str, 'SPT'))
+    def __init__(self, npoints, mode='S'):
+        self.npoints = npoints
+        if mode == 'P':
+            self.mpcommands = ['calc_pi']
+        elif mode == 'T':
+            self.thcommands = ['calc_pi']
+        elif mode == 'S':
+            self.commands = ['calc_pi']
+        self.n_cpu = multiprocessing.cpu_count()
+    
+    def submit_tasks(self):
+        self.i = plac.Interpreter(self).__enter__()            
+        return [self.i.submit('calc_pi %d' % (self.npoints / self.n_cpu))
+                for _ in range(self.n_cpu)]
+
+    def close(self):
+        self.i.close()
+
+    @plac.annotations(
+        npoints=('npoints', 'positional', None, int))
+    def calc_pi(self, npoints):
+        counts = 0
+        for j in xrange(npoints):
+            n, r = divmod(j, 1000000)
+            if r == 0:
+                yield '%dM iterations' % n
+            x, y = random(), random()
+            if x*x + y*y < 1:
+                counts += 1
+        yield (4.0 * counts)/npoints
+
+    def run(self):
+        tasks = self.i.tasks()
+        for t in tasks:
+            t.run()
+        try:
+            total = 0
+            for task in tasks:
+                total += task.result
+        except: # the task was killed
+            print tasks
+            return
+        return total / self.n_cpu
+
+if __name__ == '__main__':
+    pc = plac.call(PiCalculator)
+    pc.submit_tasks()
+    try:
+        import time; t0 = time.time()
+        print '%f in %f seconds ' % (pc.run(), time.time() - t0)
+    finally:
+        pc.close()