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Python replace between two chars (no split function)

I currently investigate a problem that I want to replace something in a string.
For example. I have the following string:
'123.49, 19.30, 02\n'
I only want the first two numbers like '123.49, 19.30'. The split function is not possible, because a I have a lot of data and some with and some without the last number.
I tried something like this:
import re as regex
#result = regex.match(', (.*)\n', string)
result = re.search(', (.*)\\n', string)
print(result.group(1))
This is not working finde. Can someone help me?
Thanks in advance

You could do something like this:
reg=r'(\d+\.\d+), (\d+\.\d+).*'
if(re.search(reg, your_text)):
match = re.search(reg, your_text)
first_num = match.group(1)
second_num = match.group(2)

Alternatively, also adding the ^ sign at the beginning, making sure to always only take the first two.
import re
string = '123.49, 19.30, 02\n'
pattern = re.compile('^(\d*.?\d*), (\d*.?\d*)')
result = re.findall(pattern, string)
result
Output:
[('123.49', '19.30')]

In the code you are using import re as regex. If you do that, you would have to use regex.search instead or re.search.
But in this case you can just use re.
If you use , (.*) you would capture all after the first occurrence of , and you are not taking digits into account.
If you want the first 2 numbers as stated in the question '123.49, 19.30' separated by comma's you can match them without using capture groups:
\b\d+\.\d+,\s*\d+\.\d+\b
Or matching 1 or more repetitions preceded by a comma:
\b\d+\.\d+(?:,\s*\d+\.\d+)+\b
regex demo | Python demo
As re.search can also return None, you can first check if there is a result (no need to run re.search twice)
import re
regex = r"\b\d+\.\d+(?:,\s*\d+\.\d+)+\b"
s = "123.49, 19.30, 02"
match = re.search(regex, s)
if match:
print(match.group())
Output
123.49, 19.30

Split according to regex condition

This will be my another question:
string = "Organization: S.P. Dyer Computer Consulting, Cambridge MA"
How can I take all the characters despite it being fullstop, digits, or anything after "Organization: " using regex?
result_organization = re.search("(Organization: )(\w*\.*\w*\.*\w*\s*\w*\s*\w*\s*)", string)
My above code is super long and not wise at all.

I would recommend using find command like this
print(string[string.find("Organization")+14:])

You don't need regex for that, this simple code should give you desired result:
str = "Organization: S.P. Dyer Computer Consulting, Cambridge MA";
if str.startswith("Organization: "):
str = str[14:];
print(str)
You also could use pattern (?<=Organization: ).+
Explanation:
(?<=Organization: ) - positive lookbehind, asserts if what is preceeding is Organization:
.+ - match any character except for newline characters.
Demo

You could use a single capturing group instead of 2 capturing groups.
Instead of specify all the words (\w*\.*\w*\.*\w*\s*\w*\s*\w*\s*) you might choose to match any character except a newline using the dot and then match the 0+ times to match until the end.
But note that that would also match strings like ##$$ ++
^Organization: (.+)
Regex demo | Python demo
For example
import re
string = "Organization: S.P. Dyer Computer Consulting, Cambridge MA"
result_organization = re.search("Organization: (.*)", string)
print(result_organization.group(1))
If you want a somewhat more restrictive pattern you might use a character class and specify what you would allow to match. For example:
^Organization: ([\w.,]+(?: [\w.,]+)*)
Regex demo

Python regex to match after the text and the dot [duplicate]

I am using Python and would like to match all the words after test till a period (full-stop) or space is encountered.
text = "test : match this."
At the moment, I am using :
import re
re.match('(?<=test :).*',text)
The above code doesn't match anything. I need match this as my output.

Everything after test, including test
test.*
Everything after test, without test
(?<=test).*
Example here on regexr.com

You need to use re.search since re.match tries to match from the beging of the string. To match until a space or period is encountered.
re.search(r'(?<=test :)[^.\s]*',text)
To match all the chars until a period is encountered,
re.search(r'(?<=test :)[^.]*',text)

In a general case, as the title mentions, you may capture with (.*) pattern any 0 or more chars other than newline after any pattern(s) you want:
import re
p = re.compile(r'test\s*:\s*(.*)')
s = "test : match this."
m = p.search(s) # Run a regex search anywhere inside a string
if m: # If there is a match
print(m.group(1)) # Print Group 1 value
If you want . to match across multiple lines, compile the regex with re.DOTALL or re.S flag (or add (?s) before the pattern):
p = re.compile(r'test\s*:\s*(.*)', re.DOTALL)
p = re.compile(r'(?s)test\s*:\s*(.*)')
However, it will retrun match this.. See also a regex demo.
You can add \. pattern after (.*) to make the regex engine stop before the last . on that line:
test\s*:\s*(.*)\.
Watch out for re.match() since it will only look for a match at the beginning of the string (Avinash aleady pointed that out, but it is a very important note!)
See the regex demo and a sample Python code snippet:
import re
p = re.compile(r'test\s*:\s*(.*)\.')
s = "test : match this."
m = p.search(s) # Run a regex search anywhere inside a string
if m: # If there is a match
print(m.group(1)) # Print Group 1 value
If you want to make sure test is matched as a whole word, add \b before it (do not remove the r prefix from the string literal, or '\b' will match a BACKSPACE char!) - r'\btest\s*:\s*(.*)\.'.

I don't see why you want to use regex if you're just getting a subset from a string.
This works the same way:
if line.startswith('test:'):
print(line[5:line.find('.')])
example:
>>> line = "test: match this."
>>> print(line[5:line.find('.')])
match this
Regex is slow, it is awkward to design, and difficult to debug. There are definitely occassions to use it, but if you just want to extract the text between test: and ., then I don't think is one of those occasions.
See: https://softwareengineering.stackexchange.com/questions/113237/when-you-should-not-use-regular-expressions
For more flexibility (for example if you are looping through a list of strings you want to find at the beginning of a string and then index out) replace 5 (the length of 'test:') in the index with len(str_you_looked_for).

Python re.finditer match.groups() does not contain all groups from match

I am trying to use regex in Python to find and print all matching lines from a multiline search.
The text that I am searching through may have the below example structure:
AAA
ABC1
ABC2
ABC3
AAA
ABC1
ABC2
ABC3
ABC4
ABC
AAA
ABC1
AAA
From which I want to retrieve the ABC*s that occur at least once and are preceeded by an AAA.
The problem is, that despite the group catching what I want:
match = <_sre.SRE_Match object; span=(19, 38), match='AAA\nABC2\nABC3\nABC4\n'>
... I can access only the last match of the group:
match groups = ('AAA\n', 'ABC4\n')
Below is the example code that I use for this problem.
#! python
import sys
import re
import os
string = "AAA\nABC1\nABC2\nABC3\nAAA\nABC1\nABC2\nABC3\nABC4\nABC\nAAA\nABC1\nAAA\n"
print(string)
p_MATCHES = []
p_MATCHES.append( (re.compile('(AAA\n)(ABC[0-9]\n){1,}')) ) #
matches = re.finditer(p_MATCHES[0],string)
for match in matches:
strout = ''
gr_iter=0
print("match = "+str(match))
print("match groups = "+str(match.groups()))
for group in match.groups():
gr_iter+=1
sys.stdout.write("TEST GROUP:"+str(gr_iter)+"\t"+group) # test output
if group is not None:
if group != '':
strout+= '"'+group.replace("\n","",1)+'"'+'\n'
sys.stdout.write("\nCOMPLETE RESULT:\n"+strout+"====\n")

Here is your regular expression:
(AAA\r\n)(ABC[0-9]\r\n){1,}
Debuggex Demo
Your goal is to capture all ABC#s that immediately follow AAA. As you can see in this Debuggex demo, all ABC#s are indeed being matched (they're highlighted in yellow). However, since only the "what is being repeated" part
ABC[0-9]\r\n
is being captured (is inside the parentheses), and its quantifier,
{1,}
is not being captured, this therefore causes all matches except the final one to be discarded. To get them, you must also capture the quantifier:
AAA\r\n((?:ABC[0-9]\r\n){1,})
Debuggex Demo
I've placed the "what is being repeated" part (ABC[0-9]\r\n) into a non-capturing group. (I've also stopped capturing AAA, as you don't seem to need it.)
The captured text can be split on the newline, and will give you all the pieces as you wish.
(Note that \n by itself doesn't work in Debuggex. It requires \r\n.)
This is a workaround. Not many regular expression flavors offer the capability of iterating through repeating captures (which ones...?). A more normal approach is to loop through and process each match as they are found. Here's an example from Java:
import java.util.regex.*;
public class RepeatingCaptureGroupsDemo {
public static void main(String[] args) {
String input = "I have a cat, but I like my dog better.";
Pattern p = Pattern.compile("(mouse|cat|dog|wolf|bear|human)");
Matcher m = p.matcher(input);
while (m.find()) {
System.out.println(m.group());
}
}
}
Output:
cat
dog
(From http://ocpsoft.org/opensource/guide-to-regular-expressions-in-java-part-1/, about a 1/4 down)
Please consider bookmarking the Stack Overflow Regular Expressions FAQ for future reference. The links in this answer come from it.

You want the pattern of consecutive ABC\n occurring after a AAA\n in the most greedy way. You also want only the group of consecutive ABC\n and not a tuple of that and the most recent ABC\n. So in your regex, exclude the subgroup within the group.
Notice the pattern, write the pattern that represents the whole string.
AAA\n(ABC[0-9]\n)+
Then capture the one you are interested in with (), while remembering to exclude subgroup(s)
AAA\n((?:ABC[0-9]\n)+)
You can then use either findall() or finditer(). I find findIter easier especially when you are dealing with more than one capture.
finditer:-
import re
matches_iter = re.finditer(r'AAA\n((?:ABC[0-9]\n)+)', string)
[print(i.group(1)) for i in matches_iter]
findall, used the original {1,} as its a more verbose form of + :-
matches_all = re.findall(r'AAA\n((?:ABC[0-9]\n){1,})', string)
[[print(x) for x in y.split("\n")] for y in matches_all]

python regex: get end digits from a string

I am quite new to python and regex (regex newbie here), and I have the following simple string:
s=r"""99-my-name-is-John-Smith-6376827-%^-1-2-767980716"""
I would like to extract only the last digits in the above string i.e 767980716 and I was wondering how I could achieve this using python regex.
I wanted to do something similar along the lines of:
re.compile(r"""-(.*?)""").search(str(s)).group(1)
indicating that I want to find the stuff in between (.*?) which starts with a "-" and ends at the end of string - but this returns nothing..
I was wondering if anyone could point me in the right direction..
Thanks.

You can use re.match to find only the characters:
>>> import re
>>> s=r"""99-my-name-is-John-Smith-6376827-%^-1-2-767980716"""
>>> re.match('.*?([0-9]+)$', s).group(1)
'767980716'
Alternatively, re.finditer works just as well:
>>> next(re.finditer(r'\d+$', s)).group(0)
'767980716'
Explanation of all regexp components:
.*? is a non-greedy match and consumes only as much as possible (a greedy match would consume everything except for the last digit).
[0-9] and \d are two different ways of capturing digits. Note that the latter also matches digits in other writing schemes, like ୪ or ൨.
Parentheses (()) make the content of the expression a group, which can be retrieved with group(1) (or 2 for the second group, 0 for the whole match).
+ means multiple entries (at least one number at the end).
$ matches only the end of the input.

Nice and simple with findall:
import re
s=r"""99-my-name-is-John-Smith-6376827-%^-1-2-767980716"""
print re.findall('^.*-([0-9]+)$',s)
>>> ['767980716']
Regex Explanation:
^ # Match the start of the string
.* # Followed by anthing
- # Upto the last hyphen
([0-9]+) # Capture the digits after the hyphen
$ # Upto the end of the string
Or more simply just match the digits followed at the end of the string '([0-9]+)$'

Your Regex should be (\d+)$.
\d+ is used to match digit (one or more)
$ is used to match at the end of string.
So, your code should be: -
>>> s = "99-my-name-is-John-Smith-6376827-%^-1-2-767980716"
>>> import re
>>> re.compile(r'(\d+)$').search(s).group(1)
'767980716'
And you don't need to use str function here, as s is already a string.

Use the below regex
\d+$
$ depicts the end of string..
\d is a digit
+ matches the preceding character 1 to many times

Save the regular expressions for something that requires more heavy lifting.
>>> def parse_last_digits(line): return line.split('-')[-1]
>>> s = parse_last_digits(r"99-my-name-is-John-Smith-6376827-%^-1-2-767980716")
>>> s
'767980716'

I have been playing around with several of these solutions, but many seem to fail if there are no numeric digits at the end of the string. The following code should work.
import re
W = input("Enter a string:")
if re.match('.*?([0-9]+)$', W)== None:
last_digits = "None"
else:
last_digits = re.match('.*?([0-9]+)$', W).group(1)
print("Last digits of "+W+" are "+last_digits)

Try using \d+$ instead. That matches one or more numeric characters followed by the end of the string.