#!/bin/python

"""
Demonstration of relative performance of copying an array via the constructor
and other methods.
"""

from array import array
import timeit

my_array = array('B', 'X' * 1000000)

def by_constructor(a):
    """Copy via the constructor.  This is slow!"""
    return array('B', a)

def by_slice(a):
    """Copy via slicing."""
    return a[:]

def by_string(a):
    """Convert to a string and back again."""
    b = array('B')

    b.fromstring(a.tostring())

    return b


if __name__=='__main__':
    from timeit import Timer

    LOOPS = 100
    t = Timer("by_constructor(my_array)", "from __main__ import by_constructor, my_array")
    print "Constructor: ", t.timeit(LOOPS)
    t = Timer("by_slice(my_array)", "from __main__ import by_slice, my_array")
    print "Slice: ", t.timeit(LOOPS)
    t = Timer("by_string(my_array)", "from __main__ import by_string, my_array")
    print "String: ", t.timeit(LOOPS)