I have following string GA1.2.4451363243.9414195136 and I want to match 4451363243.9414195136 using regular expression for python.

I have tried the following which is not working ([\d].[\d])$

Where am I going wrong here?

CodePudding user response：

A few ideas (string operations or regex):

s = 'GA1.2.4451363243.9414195136'

out = '.'.join(s.rsplit('.', 2)[-2:])
# '4451363243.9414195136'

import re
out = re.search(r'[^.]*\.[^.]*$', s)
# <re.Match object; span=(6, 27), match='4451363243.9414195136'>

NB. to ensure matching digits, you can replace [^.] (any character but .) with \d.

For an arbitrary N:

N = 3

out = '.'.join(s.rsplit('.', N)[-N:])
# '2.4451363243.9414195136'

out = re.search(fr'[^.]*(?:\.[^.]*){{{N-1}}}$', s)
# <re.Match object; span=(4, 27), match='2.4451363243.9414195136'>

CodePudding user response：

It could be done using pure python! but if you want to use regex here is the code:

regex:

(?:[\w\d]*.){2}(.*)

python:

import re
s = 'GA1.2.4451363243.9414195136'
re.match(r'(?:[\w\d]*.){2}(.*)',s).groups()[0]   # output: '4451363243.9414195136'

OR

Just use python:

s.split('.',2)[-1]    # output: '4451363243.9414195136'

CodePudding user response：

The following regex ([0-9] .[0-9] )$ matches the expected part of the example. Note that more specific solutions may arise as you provide more details, restrictions, etc. regarding the part to be matched:

>>> import re
>>> data = "GA1.2.4451363243.941419513"
>>> re.findall(r"([0-9] .[0-9] )$", data)
['4451363243.941419513']

It requests the matched part to be made of:

digit(s)
dot
digit(s)
end of line.