#!/usr/bin/env python

""" clockres - calculates the resolution in seconds of a given timer.

    Copyright (c) 2006, Marc-Andre Lemburg (mal@egenix.com). See the

    documentation for further information on copyrights, or contact

    the author. All Rights Reserved.

"""

import time

TEST_TIME = 1.0

def clockres(timer):

    d = {}

    wallclock = time.time

    start = wallclock()

    stop = wallclock() + TEST_TIME

    spin_loops = range(1000)

    while 1:

        now = wallclock()

        if now >= stop:

            break

        for i in spin_loops:

            d[timer()] = 1

    values = d.keys()

    values.sort()

    min_diff = TEST_TIME

    for i in range(len(values) - 1):

        diff = values[i+1] - values[i]

        if diff < min_diff:

            min_diff = diff

    return min_diff

if __name__ == '__main__':

    print 'Clock resolution of various timer implementations:'

    print 'time.clock:           %10.3fus' % (clockres(time.clock) * 1e6)

    print 'time.time:            %10.3fus' % (clockres(time.time) * 1e6)

    try:

        import systimes

        print 'systimes.processtime: %10.3fus' % (clockres(systimes.processtime) * 1e6)

    except ImportError:

        pass