用于浮点数或整数的 Python 正则表达式，同时不将浮点数拆分为两个浮点数 [英] Python regex for float or int while not splitting the float into two floats

问题描述

我正在尝试从一个可以是 int 或 float 的文件中提取数据.我发现这个正则表达式将从文件 (\d+(\.\d+)?) 中提取这两种类型，但我遇到的问题是它将浮点数拆分为两个.

<预><代码>>>>进口重新>>>line = "(gr_line (start 218.948 126.111) (end 218.948 143.637) (angle 90) (layer Edge.Cuts) (width 0.1) (tstamp 53D2B530))">>>>>>打印 re.findall(r'\(start (\d+(\.\d+)?) (\d+(\.\d+)?)\)', line)[('218.948', '.948', '126.111', '.111')]>>>

这样做的目的是获取由 (start nn) 定义的起始坐标，但正如你所看到的，它取了 218.948 并将其拆分为 218.948 和 .948.126.111 也有同样的问题.

如果输入字符串的起始括号中有一个 int，我得到以下内容:

<预><代码>>>>line = "(gr_line (start 218.948 126) (end 218.948 143.637) (angle 90) (layer Edge.Cuts) (width 0.1) (tstamp 53D2B530))">>>打印 re.findall(r'\(start (\d+(\.\d+)?) (\d+(\.\d+)?)\)', line)[('218.948', '.948', '126', '')]>>>

这里的问题是添加的空索引 - 不是一个大问题，但有点不方便.

我如何格式化我的正则表达式，以便它捕获一个浮点数并返回该浮点数，或一个 int 并返回该整数.

解决方案

您正在使用 (\d+(\.\d+)?)

捕获和保存两个分组

试试这个:

(\d+(?:\.\d+)?)

这只会保存整个浮动中的分组.

I'm trying to pull data from a file that can either be an int or a float. I've found this regex that will pull these two types from the file (\d+(\.\d+)?), but the problem I'm having with it is that it's splitting the floats into two.

>>> import re
>>> line = "(gr_line (start 218.948 126.111) (end 218.948 143.637) (angle 90) (layer Edge.Cuts) (width 0.1) (tstamp 53D2B530))"
>>>
>>> print re.findall(r'\(start (\d+(\.\d+)?) (\d+(\.\d+)?)\)', line)
[('218.948', '.948', '126.111', '.111')]
>>>

The purpose of this is to get the starting coordinates which are defined by (start n n), but as you can see, it's taking 218.948 and splitting it into 218.948 and .948. Same issue with 126.111.

If the input string has an int in the starting brackets, I get the following:

>>> line = "(gr_line (start 218.948 126) (end 218.948 143.637) (angle 90) (layer Edge.Cuts) (width 0.1) (tstamp 53D2B530))"
>>> print re.findall(r'\(start (\d+(\.\d+)?) (\d+(\.\d+)?)\)', line)
[('218.948', '.948', '126', '')]
>>>

The issue here is the added empty index - not a huge problem, but a little inconvenient.

How can I format my regex so it captures either a float and return that float, or an int and return that int.

解决方案

You're capturing and saving two groupings with (\d+(\.\d+)?)

Try this:

(\d+(?:\.\d+)?)

That will only save the grouping from the entire float.

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