#!/usr/bin/env python

# Simple script to run another command a certain number of times,
# recording how long each run took, and writing the results out to a file.

import os
import os.path
import re
import string
import sys
import time

__author__ = "Peter Maxwell and  Gavin Huttley"
__copyright__ = "Copyright 2007-2012, The Cogent Project"
__credits__ = ["Peter Maxwell", "Gavin Huttley", "Edward Lang"]
__license__ = "GPL"
__version__ = "1.5.3"
__maintainer__ = "Gavin Huttley"
__email__ = "gavin.huttley@anu.edu.au"
__status__ = "Production"

# Values that affect the running of the program.
minimum_accepted_time = 2

iterations = int(sys.argv[1])
args = sys.argv[2:]

script_re = re.compile(".py$")
type = ""

for i in range(len(args)):
    if script_re.search(args[i], 1):
        script = args[i][0:string.index(args[i], '.')]
    if args[i] == "mpirun":
        type = "parallel"

if not type:
    type = "serial"

output = "timing/" + script + "-" + str(int(time.time())) + "-" + type

def usage():
    pass

def standard_dev(numbers = [], mean = 1):
    import math
    
    sum = 0
    
    for i in range(len(numbers)):
        sum = sum + math.pow(numbers[i] - mean, 2)

    sigma = math.sqrt(sum / (len(numbers) - 1))

    return sigma
    
def main():
    if args:
        command = ' '.join(map(str, args))
    else:
        usage()
        sys.exit()

    total_time = 0.0
    times = []

    print 'Running "%s" %d times...' % (command, iterations)
    i = 0
    attempt = 0
    while i < iterations:
        start_time  = time.time()
        os.system(command + " > " + output + "." + str(i))
        end_time    = time.time() - start_time

        if end_time > minimum_accepted_time:
            times.append(end_time)
            total_time  = total_time + end_time
            print "Time for run %d: %.3f seconds" % (i, end_time)
            i = i + 1
            attempt = 0
        else:
            print "Discarding probably bogus time: %.3f seconds" % end_time
            attempt = attempt + 1
        if attempt == 5:
            print "Aborting early due to multiple errors"
            sys.exit(3)
            
    times.sort()
    mean = total_time / len(times)
    sd   = standard_dev(times, mean)
    print ""
    print "Fastest time   : %.3f" % times[0]
    print "Slowest time   : %.3f" % times[len(times) - 1]
    print "Mean           : %.3f" % mean
    print "Standard dev   : %.3f" % sd
    print "Total time     : %.3f" % total_time

    print ""

    corrected_total = 0.0
    corrected_times = []

    for i in range(len(times)):
        if abs(mean - times[i]) < sd:
            corrected_times.append(times[i])
            corrected_total = corrected_total + times[i]
        else:
            print "Discarding value '%.3f'" % times[i]

    if len(times) != len(corrected_times):
        corrected_mean = corrected_total / len(corrected_times)
        corrected_sd   = standard_dev(corrected_times, corrected_mean)
    
        print ""
        print "CORRECTED RESULTS"
        print "Fastest time   : %.3f" % corrected_times[0]
        print "Slowest time   : %.3f" % corrected_times[len(corrected_times)-1]
        print "Mean           : %.3f" % corrected_mean
        print "Standard dev   : %.3f" % corrected_sd
    
if __name__ == "__main__":
    main()