Split a string if character is present else don't split-CodePudding

I have a string like below in python

testing_abc

I want to split string based on _ and extract the 2 element

I have done like below

split_string = string.split('_')[1]

I am getting the correct output as expected

abc

Now I want this to work for below strings

1) xyz

When I use

split_string = string.split('_')[1]

I get below error

list index out of range

expected output I want is xyz

2) testing_abc_bbc

When I use

split_string = string.split('_')[1]

I get abc as output

expected output I want is abc_bbc

Basically What I want is

1) If string contains `_` then print everything after the first `_` as variable
2) If string doesn't contain `_` then print the string as variable

How can I achieve what I want

CodePudding user response：

Set the maxsplit argument of split to 1 and then take the last element of the resulting list.

>>> "testing_abc".split("_", 1)[-1]
'abc'
>>> "xyz".split("_", 1)[-1]
'xyz'
>>> "testing_abc_bbc".split("_", 1)[-1]
'abc_bbc'

CodePudding user response：

You can use list slicing and str.join in case _ is in the string, and you can just get the first element of the split (which is the only element) in the other case:

sp = string.split('_')
result = '_'.join(sp[1:]) if len(sp) > 1 else sp[0]

CodePudding user response：

All of the ways are good but there is a very simple and optimum way for this.

Try:

s = 'aaabbnkkjbg_gghjkk_ttty'
try:
    ans = s[s.index('_'):]
except:
    ans = s

CodePudding user response：

Ok so your error is supposed to happen/expected because you are using '_' as your delimiter and it doesn't contain it. See How to check a string for specific characters? for character checking.

If you want to only split iff the string contains a '_' and only on the first one,

input_string = "blah_end"
delimiter = '_'

if delimiter in input_string:
     result = input_string.split("_", 1)[1] # The ",1" says only split once
else:
     # Do whatever here. If you want  a space, " " to be a delimiter too you can try that.
     result = input_string

CodePudding user response：

this code will solve your problem

txt = "apple_banana_cherry_orange"
# setting the maxsplit parameter to 1, will return a list with 2 elements!
x = txt.split("_", 1)
print(x[-1])