作为python开发,range和xrange的区别?


在Python 2中,range和xrange都是用来生成一个整数序列的函数,但是在使用方式和功能上有一些区别。 range函数会生成一个列表,列表中包含了从start到stop-1的所有整数,步长默认为1。例如,range(5)会生成[0, 1, 2, 3, 4]。range函数生成的列表会占用大量的内存,如果需要生成的序列非常大,可能会导致内存溢出。 xrange函数则不会生成一个完整的列表,而是生成一个迭代器,每次迭代返回序列中的下一个整数。例如,xrange(5)会生成一个迭代器,可以像遍历列表一样遍历这个迭代器,但是不会一次性生成所有的整数,这样可以节省大量的内存。 在Python 3中,range函数的行为和xrange函数类似,会生成一个迭代器,不会一次性生成所有的整数。Python 3中已经没有了xrange函数。 [2023-11-08 00:47:31 | AI写代码神器 | 208点数解答]
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