在Python 2.7。和3.3(复制)

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Python division 11 answers
Python部门11日答案

How can I divide two numbers in Python 2.7 and get the result with decimals?

我如何用Python 2。7除以两个数，得到小数的结果?

I don't get it why there is difference:

我不明白为什么会有差异

in Python 3:

在Python 3:

>>> 20/15
1.3333333333333333

in Python 2:

在Python中2:

>>> 20/15
1

Isn't this a modulo actually?

这不是一个模吗?

4 个解决方案

#1

In python 2.7, the / operator is integer division if inputs are integers.

在python 2.7中，如果输入是整数，则/运算符是整数除法。

If you want float division (which is something I always prefer), just use this special import:

如果你想要浮动除法(这是我一直喜欢的)，请使用这个特殊的导入:

from __future__ import division

See it here:

看这里:

>>> 3 / 2
1
>>> from __future__ import division
>>> 3 / 2
1.5
>>>

Integer division is achieved by using //, and modulo by using %

整数除法是通过使用//和使用%来实现的

>>> 3 % 2
1
>>> 3 // 1
3
>>>

EDIT

编辑

As commented by user2357112, this import has to be done before any other normal import.

正如user2357112所评论的，这个导入必须在任何其他正常导入之前完成。

#2

In Python 3, / is float division

在Python 3中，/是浮点除法

In Python 2, / is integer division (assuming int inputs)

在Python 2中，/是整数除法(假设int输入)

In both 2 and 3, // is integer division

在2和3中，//是整数除法。

(To get float division in Python 2 requires either of the operands be a float, either as 20. or float(20))

(要在Python 2中获得浮点除法，需要其中任何一个操作数都是浮点数，或者是20。或浮动(20))

#3

In Python 2.x, make sure to have at least one operand of your division in float. Multiple ways you may achieve this as the following examples:

在Python中2。x，确保在浮点数中至少有一个除法的操作数。你可以通过多种方式实现这个目标，如下所示:

20. / 15
20 / float(15)

#4

"/" is integer division in python 2 so it is going to round to a whole number. If you would like a decimal returned, just change the type of one of the inputs to float:

“/”是python 2中的整数除法，因此它将转到整数。如果您希望返回一个十进制数，只需将其中一个输入的类型更改为float:

float(20)/15 #1.33333333

(20)/ 15 # 1.33333333浮动

#1