How to Extract the Substring Between Two Markers

How to extract the substring between two markers?

Using regular expressions - documentation for further reference

import re

text = 'gfgfdAAA1234ZZZuijjk'

m = re.search('AAA(.+?)ZZZ', text)
if m:
    found = m.group(1)

# found: 1234

or:

import re

text = 'gfgfdAAA1234ZZZuijjk'

try:
    found = re.search('AAA(.+?)ZZZ', text).group(1)
except AttributeError:
    # AAA, ZZZ not found in the original string
    found = '' # apply your error handling

# found: 1234

Extract all substrings between two markers

What could I do to resolve this?
I would do:

import re
mystr = "&marker1\nThe String that I want /\n&marker1\nAnother string that I want /\n"
found = re.findall(r"\&marker1\n(.*?)/\n", mystr)
print(found)

Output:

['The String that I want ', 'Another string that I want ']

Note that:

• & has special meaning in re patterns, if you want literal & you need to escape it (\&)
• . does match anything except newlines
• findall is better suited choiced if you just want list of matched substrings, rather than search
• *? is non-greedy, in this case .* would work too, because . do not match newline, but in other cases you might ending matching more than you wish
• I used so-called raw-string (r-prefixed) to make escaping easier

Read module re documentation for discussion of raw-string usage and implicit list of characters with special meaning.

How to get the substring between two markers in Python multiple times?

you can use regex

import re
s = '''alt="Thunder Force"/>ehkjehkljhiflealt="Godzilla vs. Kong"/>'''
x = re.findall(r'alt="(.*?)"/>', s)
print(x)

output

['Thunder Force', 'Godzilla vs. Kong']

Extract all substrings between two markers for a very long string

I couldn't get re.findall to work. Now I do use re but to find the location of markers and extract the substrings manually.

locs_start = [match.start() for match in re.finditer("\&marker1", mylongstring)]
locs_end = [match.start() for match in re.finditer("/\n", mylongstring)]

substrings = []
for i in range(0, len(locs_start)):
    substrings.append(mylongstring[locs_start[i]:locs_end[i]+1])

Find string between two substrings

import re

s = 'asdf=5;iwantthis123jasd'
result = re.search('asdf=5;(.*)123jasd', s)
print(result.group(1))

How to capture multiple substrings between two markers using regular expressions?

You need a regex method that will find all the matches in a string. You should try re.findall('\$\{(.+?)\}', text) or re.finditer('\$\{(.+?)\}', text). The first will return a list, the second will return an iterable.

extract text between two markers in a pandas column

You can use

df[0].str.extract(r'\((\w+),', expand=False)

See the regex demo.

The regex matches one or more letters/digits/underscores between a ( and , chars. Since Series.str.extract requires a capturing group in a regex pattern, there \w+ is enclosed with two unescape capturing parentheses.

---

Related Topics