Print the geometric mean

tools/measure_perf.py

@@ -4,14 +4,27 @@ import subprocess
 import time
 
 def run_tests(executables, benchmarks):
+    times = [[] for e in executables]
+
     for b in benchmarks:
-        for e in executables:
+        for e, time_list in zip(executables, times):
             start = time.time()
             subprocess.check_call(e + [b], stdout=open("/dev/null", 'w'))
             elapsed = time.time() - start
 
             print "%s %s: % 4.1fs" % (" ".join(e).rjust(25), b.ljust(35), elapsed)
 
+            time_list.append(elapsed)
+
+    for e, time_list in zip(executables, times):
+        t = 1
+        for elapsed in time_list:
+            t *= elapsed
+        t **= (1.0 / len(time_list))
+        print "%s %s: % 4.1fs" % (" ".join(e).rjust(25), "geomean".ljust(35), t)
+
+
+
 def main():
     executables = [["./pyston_release", "-q"]]