python之函数用法xrange()，,# -*- codi

python之函数用法xrange()，,# -*- codi

# -*- coding: utf-8 -*-#python 27#xiaodeng#python之函数用法xrange()#xrange()#说明：返回一个生成器#xrange做循环的性能比range好,尤其是返回很大的时候.除非要返回一个列表,则用range.‘‘‘class xrange(object) |  xrange(stop) -> xrange object |  xrange(start, stop[, step]) -> xrange object |   |  Like range(), but instead of returning a list, returns an object that |  generates the numbers in the range on demand.  For looping, this is  |  slightly faster than range() and more memory efficient.‘‘‘#案例x= xrange(5)            #xrange(5)-> xrange对象print list(x)           #[0, 1, 2, 3, 4]

python之函数用法xrange()