在 python range() 中是否有任何方法，如除以或乘以?

问题描述

for java, we can do:

for(int i=100; i>2 ; i=i/2){things to execute}

but what if in python?

is there anything like

for i in range(100:2:something)

could solve this problem?

解决方案

If you need something simple which you can have at hand at several places, you can create a generator function:

def range_divide(start, end, denominator): # TODO: Think for a better name!
    value = start
    while value > end:
        yield value
        value /= denominator

and then do

for value in range_divide(100, 2, 2):
    # do_stuff

You could even flexibilize this with

def range_flexible(start, end, action):
    value = start
    while value > end:
        yield value
        value = action(value)

and do

for value in range_flexible(100, 2, lambda x: x/2):
    # do_stuff

or even

def for_loop(start, cont_condition, action):
    value = start
    while cont_condition(value):
        yield value
        value = action(value)

for value in for_loop(100, lambda x: x > 2, lambda x: x/2):
    # do_stuff