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Capture the n previous words when matching a string

Let's say I have this text:
abcdefg Mark Jones (PP) etc etc
akslaskAS Taylor Daniel Lautner (PMB) blabla
etcetc Allan Stewart Konigsberg Farrow (PRTW)
I want to capture these personal names:
Mark Jones, Taylor Daniel Lautner, Allan Stewart Konigsberg Farrow.
Basically, when we find (P followed by any capital letter, we capture the n previous words that start with a capital letter.
What I have achieved so far is to capture just one previous word with this code: \w+(?=\s+(\(P+[A-Z])). But I couldn't evolve from that.
I appreciate it if someone can help :)

Regex pattern
\b((?:[A-Z]\w+\s?)+)\s\(P[A-Z]
In order to find all matching occurrences of the above regex pattern we can use re.findall
import re
text = """abcdefg Mark Jones (PP) etc etc
akslaskAS Taylor Daniel Lautner (PMB) blabla
etcetc Allan Stewart Konigsberg Farrow (PRTW)
"""
matches = re.findall(r'\b((?:[A-Z]\w+\s?)+)\s\(P[A-Z]', text)
>>> matches
['Mark Jones', 'Taylor Daniel Lautner', 'Allan Stewart Konigsberg Farrow']
Regex details
\b : Word boundary to prevent partial matches
((?:[A-Z]\w+\s?)+): First Capturing group
(?:[A-Z]\w+\s?)+: Non capturing group matches one or more times
[A-Z]: Matches a single alphabet from capital A to Z
\w+: Matches any word character one or more times
\s? : Matches any whitespace character zero or one times
\s : Matches a single whitespace character
\(: Matches the character ( literally
P : Matches the character P literally
[A-Z] : Matches a single alphabet from capital A to Z
See the online regex demo

With your shown samples, could you please try following. Using Python's re library here to fetch the results. Firstly using findall to fetch all values from given string var where (.*?)\s+\((?=P[A-Z]) will catch everything which is having P and a capital letter after it, then creating a list lst. Later using substitute function to substitute everything non-spacing things followed by spaces 1st occurrences with NULL to get exact values.
import re
var="""abcdefg Mark Jones (PP) etc etc
akslaskAS Taylor Daniel Lautner (PMB) blabla
etcetc Allan Stewart Konigsberg Farrow (PRTW)"""
lst = re.findall(r'(.*?)\s+\((?=P[A-Z])',var)
[re.sub(r'^\S+\s+','',s) for s in lst]
Output will be as follows:
['Mark Jones', 'Taylor Daniel Lautner', 'Allan Stewart Konigsberg Farrow']

Python regex for matching arbitrary number of elements between 2 substrings?

I'm trying to write a regex which finds all characters between a starting token ('MS' or 'PhD') and an ending token ('.' or '!'). What makes this tricky is that it's fairly common for both starting tokens to be present in my text data, I'm only interested in the characters bounded by the last starting token and first ending token. (And all such occurrences.)
start = 'MS|PhD'
end = '.|!'
input1 = "Candidate with MS or PhD in Statistics, Computer Science, or similar field."
output1 = "in Statistics, Computer Science, or similar field"
input2 = "Applicant with MS in Biology or Chemistry desired."
output2 = "in Biology or Chemistry desired"
Here's my best attempt, which is currently returning an empty list:
# start any char end
pattern = r'^(MS|PhD) .* (\.|!)$'
re.findall(pattern,"candidate with MS in Chemistry.")
>>>
[]
Could someone point me in the right direction?

You could use a capturing group and match MS or PhD and the . or ! outside of the group.
\b(?:MS|PhD)\s*((?:(?!\b(?:MS|PhD)\b).)*)[.,]
\b(?:MS|PhD)\s* A word boundary, match either MS or phD followed by 0+ leading whitspace chars to not capture them in the group
( capture group 1, which contains the desired value
(?: Non capture group
(?!\b(?:MS|PhD)\b). Match any char except a newline if it is not followed by either MS or phD
)* Close the non capture group and repeat it 0+ times
)[.,] Close group 1 and match either . or ,
Regex demo | Python demo
import re
regex = r"\b(?:MS|PhD)\s*((?:(?!\b(?:MS|PhD)\b).)*)[.,]"
s = ("Candidate with MS or PhD in Statistics, Computer Science, or similar field.\n"
"Applicant with MS in Biology or Chemistry desired.")
matches = re.findall(regex, s)
print(matches)
Output
['in Statistics, Computer Science, or similar field', 'in Biology or Chemistry desired']

Regex for python: how do I extract a string between words?

Suppose I have a sentence:
Meet me at 201 South First St. at noon
And I want to get the address like this:
South First
What would be the appropriate Regex expression for it ? I currently have this, but it is not working:
x = re.search(r"\d+\s?=([A-Z][a-z]*)\s(Rd.|Dr.|Ave.|St.)",searchstring)
Where searchstring is the sentence. The address is always preceded by 1 or more digits followed by a space and followed by either Rd. Dr. Ave. or St. The address also always starts with a capital letter.

The first group, the part where you try to match the address is [A-Z][a-z]*, it means one uppercase letter followed by any lowercase letters. Probably what you want is any uppercase or lowercase letter or space: [A-Za-z ]*. Also note that the dots in the second group mean any character and not the literal ., so you have to escape it. The solution would look like this:
>>> re.search(r'\d+\s?([A-Za-z ]*)\s+(Rd|Dr|Ave|St)\.', 'Meet me at 201 South First St. at noon')[1]
'South First'
Or just use . to accept anything.
>>> re.search(r'\d+\s?(.*?)\s+(Rd|Dr|Ave|St)\.', 'Meet me at 201 South First St. at noon')[1]
'South First'

You may use
\d+\s*([A-Z].*?)\s+(?:Rd|Dr|Ave|St)\.
See the regex demo.
Details
\d+ - one or more digits
\s* - 0 or more whitespaces
([A-Z].*?) - capturing group #1: an uppercase ASCII letter and then any 0 or more chars other than line break chars as few as possible
\s+ - 1+ whitespaces
(?:Rd|Dr|Ave|St) - Rd, Dr, Ave or St
\. - a dot
See a Python demo:
m = re.search(r'\d+\s*([A-Z].*?)\s+(?:Rd|Dr|Ave|St)\.', text)
if m:
print(m.group(1))
Output: South First.

Here is how:
import re
s = 'Meet me at 201 South First St. at noon'
print(re.findall('(?<=\d )[A-Z].*(?= d.|Dr.|Ave.|St.)', s)[0])
Output:
'South First'

How to extract first floating numbers appearing after a word?

I'm trying to build an application for text extraction use case but I was not able to extract exact price from it.
I have a text like this,
string1 = 'Friscos #8603\n8100 E. Orchard Road\nGreenwood Village, Colorado 80111\n2013-11-02\nTable 00\nGuest\n1 Oysters 1/2 Shell #1\n1 Crab Cake\n1 Filet 1602 Bone In\n1 Ribeye 22oz Bone In\n1 Asparagus\n1 Potato Au Gratin\n$17.00\n$19.00\n$66.00\n$53.00\n$12.00\n$11.50\nSub Total\nTax\n$178.50\n$12.94\nTotal\n$191.44\n'
string2 = 'Berghotel\nGrosse Scheidegg\n3818 Grindelwald\nFamilie R. Müller\nRech. Nr. 4572\nBar\n30.07.2007/13:29:17\nTisch 7/01\nNM\n#ರ\n2xLatte Macchiato à 4.50 CHF\n1xGloki\nà 5.00 CHF\n1xSchweinschnitzel à 22.00 CHF\n1xChässpätzli à 18.50 CHF\n#ರ #ರ #1ರ\n5.00\n22.00\n18.50\nTotal:\nCHF\n54.50\nIncl. 7.6% MwSt\n54.50 CHF:\n3.85\nEntspricht in Euro 36.33 EUR\nEs bediente Sie: Ursula\nMwSt Nr. : 430 234\nTel.: 033 853 67 16\nFax.: 033 853 67 19\nE-mail: grossescheidegg#bluewin.ch\n'
I want to extract the price that appearing after the word total using regex but I was only able to extract all floating numbers. Also do note some-times you may also see words such as sub total but I only need price that appears after the word total. Also sometimes after total there may occur other words as well. So Regex should match word total and extract the floating numbers that appears next to it.
Any help is appreciated.
This is what I've tried,
re.findall("\d+\.\d+", string1) # this returns all floating numbers.

You can try
(?<=\\nTotal)\:?\D+([\d\.]+)
Demo

You could try this, should work for the example and the other restrictions you mentioned
import re
result = re.search('Total\n\$(\d+.\d+)', string1)
result.group(1) # 191.44
result = re.search('Total\:\n.+\n(\d+.\d+)', string2)
result.group(1) # 54.50
EDIT: If you want only one expression for both, you could try
result = re.search('\nTotal\:?(\n\D+)*\n\$?(\d+.\d+)', string)
re.group(2)

You could use a positive lookbehind to prevent sub being before total, word boundaries to prevent the words being part of a larger word and a capturing group to capture the price.
(?<!\bsub )\btotal\b\D*(\d+(?:\.\d+))
In parts:
(?<!\bsub ) Negative lookbehind, assert what is on the left is not the word sub and a space
\btotal\b Match total between word boundaries to prevent it being part of a larger word
\D* Match 0+ times any char that is not a digit
( Capture group 1
\d+(?:\.\d+) Match 1+ digits with an optional decimal part
) Close group
Regex demo | Python demo
For example
import re
regex = r"(?<!\bsub )\btotal\b\D*(\d+(?:\.\d+))"
string1 = 'Friscos #8603\n8100 E. Orchard Road\nGreenwood Village, Colorado 80111\n2013-11-02\nTable 00\nGuest\n1 Oysters 1/2 Shell #1\n1 Crab Cake\n1 Filet 1602 Bone In\n1 Ribeye 22oz Bone In\n1 Asparagus\n1 Potato Au Gratin\n$17.00\n$19.00\n$66.00\n$53.00\n$12.00\n$11.50\nSub Total\nTax\n$178.50\n$12.94\nTotal\n$191.44\n'
string2 = 'Berghotel\nGrosse Scheidegg\n3818 Grindelwald\nFamilie R. Müller\nRech. Nr. 4572\nBar\n30.07.2007/13:29:17\nTisch 7/01\nNM\n#ರ\n2xLatte Macchiato à 4.50 CHF\n1xGloki\nà 5.00 CHF\n1xSchweinschnitzel à 22.00 CHF\n1xChässpätzli à 18.50 CHF\n#ರ #ರ #1ರ\n5.00\n22.00\n18.50\nTotal:\nCHF\n54.50\nIncl. 7.6% MwSt\n54.50 CHF:\n3.85\nEntspricht in Euro 36.33 EUR\nEs bediente Sie: Ursula\nMwSt Nr. : 430 234\nTel.: 033 853 67 16\nFax.: 033 853 67 19\nE-mail: grossescheidegg#bluewin.ch\n'
print(re.findall(regex, string1, re.IGNORECASE))
print(re.findall(regex, string2, re.IGNORECASE))
Output
['191.44']
['54.50']
If what precedes the price should be a dollar sign of the text CHF, you might use an alternation (?:\$|CHF)\s* matching of the values followed by matching 0+ whitespace chars:
(?<!\bsub )\btotal\b\D*(?:\$|CHF)\s*(\d+(?:\.\d+))
Regex demo

Something like this might do the trick:
(?<!sub )total.*?(\d+.\d+)
Make sure to ignore the case.

Why doesn't this regular expression work in all cases?

I have a text file containing entries like this:
#markwarner VIRGINIA - Mark Warner
#senatorleahy VERMONT - Patrick Leahy NO
#senatorsanders VERMONT - Bernie Sanders
#orrinhatch UTAH - Orrin Hatch NO
#jimdemint SOUTH CAROLINA - Jim DeMint NO
#senmikelee UTAH -- Mike Lee
#kaybaileyhutch TEXAS - Kay Hutchison
#johncornyn TEXAS - John Cornyn
#senalexander TENNESSEE - Lamar Alexander
I have written the following to remove the 'NO' and the dashes using regular expressions:
import re
politicians = open('testfile.txt')
text = politicians.read()
# Grab the 'no' votes
# Should be 11 entries
regex = re.compile(r'(no\s#[\w+\d+\.]*\s\w+\s?\w+?\s?\W+\s\w+\s?\w+)', re.I)
no = regex.findall(text)
## Make the list a string
newlist = ' '.join(no)
## Replace the dashes in the string with a space
deldash = re.compile('\s-*\s')
a = deldash.sub(' ', newlist)
# Delete 'NO' in the string
delno = re.compile('NO\s')
b = delno.sub('', a)
# make the string into a list
# problem with #jimdemint SOUTH CAROLINA Jim DeMint
regex2 = re.compile(r'(#[\w\d\.]*\s[\w\d\.]*\s?[\w\d\.]\s?[\w\d\.]*?\s+?\w+)', re.I)
lst1 = regex2.findall(b)
for i in lst1:
print i
When I run the code, it captures the twitter handle, state and full names other than the surname of Jim DeMint. I have stated that I want to ignore case for the regex.
Any ideas? Why is the expression not capturing this surname?

It's missing it because his state name contains two words: SOUTH CAROLINA
Have your second regex be this, it should help
(#[\w\d\.]*\s[\w\d\.]*\s?[\w\d\.]\s?[\w\d\.]*?\s+?\w+(?:\s\w+)?)
I added
(?:\s\w+)?
Which is a optional, non capturing group matching a space followed by one or more alphanumeric underscore characters
http://regexr.com?31fv5 shows that it properly matches the input with the NOs and dashes stripped
EDIT:
If you want one master regex to capture and split everything properly, after you remove the Nos and dashes, use
((#[\w]+?\s)((?:(?:[\w]+?)\s){1,2})((?:[\w]+?\s){2}))
Which you can play with here: http://regexr.com?31fvk
The full match is available in $1, the Twitter handle in $2, the State in $3 And the name in $4
Each capturing group works as follows:
(#[\w]+?\s)
This matches an # sign followed by at least one but as few characters as possible until a space.
((?:(?:[\w]+?)\s){1,2})
This matches and captures 1 or two words, which should be the state. This only works because of the next piece, which MUST have two words
((?:[\w]+?\s){2})
Matches and captures exactly two words, which is defined as few characters as possible followed by a space

text=re.sub(' (NO|-+)(?= |$)','',text)
And to capture everything:
re.findall('(#\w+) ([A-Z ]+[A-Z]) (.+?(?= #|$))',text)
Or all at once:
re.findall('(#\w+) ([A-Z ]+[A-Z])(?: NO| -+)? (.+?(?= #|$))',text)