Python: Use Regular Expression to remove a character from string

Question

The whole file consists of lines like below.

\"ansText\" : \"11\",
\"boundsX\" : 0,
\"string\" : \"11\"

For any lines starting with title, I would like to remove the character ; from the string after it. Below is an example of expected output

Input:

\"title\" : \"244442424268391(:)7)$(.:$?3.&!&3$83;767:2\",

Output:

\"title\" : \"244442424268391(:)7)$(.:$?3.&!&3$83767:2\",

I know how to set the regular expression to find the expression title by using:

 str0 = re.sub(r'\"title.*',"\"title\" : ",str0)

But I am not too certain how can I keep the original string but remove only one character.

This looks like JSON. Use JSON parser if that is the case.

nhahtdh
– nhahtdh

2016-01-07 11:08:13 +00:00
Commented Jan 7, 2016 at 11:08 — nhahtdh
– nhahtdh, Commented Jan 7, 2016 at 11:08

Remi Guan · Accepted Answer · 2016-01-07 11:14:57Z

2

You can simply do this use str.replace() and str.startswith() without RegEx like this:

>>> str0 = r'\"title\" : \"244442424268391(:)7)$(.:$?3.&!&3$83;767:2\",'
>>> str0 = str0.replace(';', '') if str0.startswith(r'\"title\" : ') else str0
>>> str0
'\\"title\\" : \\"244442424268391(:)7)$(.:$?3.&!&3$83767:2\\",'

answered Jan 7, 2016 at 11:14

Remi Guan

22.5k17 gold badges68 silver badges90 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

npinti · Accepted Answer · 2016-01-07 11:10:03Z

1

You could use something like so: (\\"title\\" : \\".+?);(.+?\\") (example here) and replace the string with regex groups number 1 and 2. This expression will look for strings containing \"title\" and a ; character within it and use this information to create two regular expression groups, this given \"title\" : \"244442424268391(:)7)$(.:$?3.&!&3$83;767:2\",, the output would be:;

Group 1: \"title\" : \"244442424268391(:)7)$(.:$?3.&!&3$83
Group 2: 767:2\"

When you combine these 2 strings, you will get the result which you are after.

 str0 = re.sub(r'(\\"title\\" : \\".+?);(.+?\\")',r"\1\2", str0)

edited Jan 7, 2016 at 11:10

answered Jan 7, 2016 at 11:08

npinti

52.2k5 gold badges74 silver badges98 bronze badges

4 Comments

Remi Guan Over a year ago

It will fails when there's more ; than one. Right?

npinti Over a year ago

@KevinGuan: It should still do what you are after, however the first ; (starting from the left) will not be included in the result.

Remi Guan Over a year ago

That's what I meant, I thought OP might want remove all ; from the string if there's more ; in the string instead of just the first one.

npinti Over a year ago

@KevinGuan: Yeah I see your point. We'll see whatever the OP decides.

Collectives™ on Stack Overflow

Python: Use Regular Expression to remove a character from string

2 Answers 2

Comments

4 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

4 Comments

Your Answer

Sign up or log in

Post as a guest

Related