In Python, how should one extract the second-last

Question

I have a string like the following:

/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisTop/2.0.24/RootCore

How should I extract the "2.0.24" from this string? I'm not sure how to split the string using the slashes (in order to extract the second last element of the resultant list) and I'm not sure if this would be a good approach. What I have right now is the following:

"/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisTop/2.0.24/RootCore".split("/RootCore")[0].split("AnalysisTop/")[1]

Answer 1

Just split according to the / symbol then print the second index from the last.

>>> x = "/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisTop/2.0.24/RootCore"
>>> y = x.split('/')
>>> y[-2]
'2.0.24'

Answer 2

cross platform solution:

import os
'/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisTop/2.0.24/RootCore'.split(os.path.sep)[-2]

Answer 3

import re

str1 = "/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisTop/2.0.24/RootCore"
t = re.findall("[0-9][.]*",str1)
print ("".join(t))

You can use regex-findall method. t returns a list, so using join().

Output;

>>> 
2.0.24
>>> 

# print (t)
>>> 
['2.', '0.', '2', '4']
>>> 

Answer 4

You can also do:

import os
x = "/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisTop/2.0.24/RootCore"
os.path.split(os.path.split(x)[0])[1]

results in

'2.0.24'

Answer 5

'/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisTop/2.0.24/RootCore'.split('/')[-2]

Answer 6

path = "/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisTop/2.0.24/RootCore"
path_dirs = path.split("/")

>>>> path_dirs
>>>> ['', 'cvmfs', 'atlas.cern.ch', 'repo', 'sw', 'ASG', 'AnalysisTop', '2.0.24', 'RootCore']

>>>> print path_dirs[-2]
>>>> '2.0.24'