使用正则表达式提取带点和逗号的数字

Question

I've read a lot of pages trying to explain me how to use the regex for Python but I still don't get it at all. Even the regex wiki and the re documentation couldn't help me at all. I'm still kind of confused :P

I have the following string:

string = "|C195|1|Base de Cálculo ST: 2.608,24 - Valor da ST: 163,66|"

I'm trying to extract only the 2.608,24 and 163,66 using:

st_values = re.findall("\d+[,.]\d+", string)

However, the output of my print st_values is:

['2.608','163,66']

Instead, I expect it to be

['2.608,24','163,66']

I don't want

['195', '1', '2.608,24','163,66']

So, how can I use the alphabet soup of regex parameters to extract them that way?

Answer 1

I suggest:

\b\d{1,3}(?:\.\d{3})*,\d+\b

Here is a demo

And here is an IDEONE code demo :

import re
p = re.compile(r'\b\d{1,3}(?:\.\d{3})*,\d+\b')
test_str = "|C195|1|Base de Cálculo ST: 2.608,24 - Valor da ST: 2.608.234,24 12.608.234,24\n  163,66|\nd2.608.234,24\n2.60d8.23d4,24"
print(re.findall(p, test_str))

Answer 2

Try this (This regex also assumes that strings like 1,23 is matched.)-

>>> re.findall("\d+(?:\.\d+)?,\d+", string)
['2.608,24', '163,66']

Regex demo and Explanation

Answer 3

if you want to extract the numbers from the second last column/field, you can do something like:

 In: re.findall(r"[0-9,.]+",string.split('|')[-2])      
Out: ['2.608,24', '163,66']

Otherwise, if you do it only with regex, and there was similar numbers in other column, you have problem to filter them out.