CODEWITHSUNDEEP
pythonlistpython-3.x
Darth
Darth

Reputation: 229

Pythonic way to search a list using keywords

I am attempting to search for text between two keywords. My solution so far is using split() to change string to list. It works but I was wondering if there is more efficient/elegant way to achieve this. Below is my code:

words = "Your meeting with Dr Green at 8pm"
list_words = words.split()
before = "with"
after = "at"
title = list_words[list_words.index(before) + 1]
name = list_words[list_words.index(after) - 1]


if title != name:
    var = title + " " + name
    print(var)
else:
    print(title)

Results: 

>>> Dr Green

Id prefer a solution that is configurable as the text I'm searching for can be dynamic so Dr Green could be replaced by a name with 4 words or 1 word.

Upvotes: 0

Views: 1376

Answers (3)

BoboDarph
BoboDarph

Reputation: 2891

How about slicing the list at start and end, then just splitting it?

words = "Your meeting with Dr Jebediah Caruseum Green at 8pm"
start = "with"
end = "at"    
list_of_stuff = words[words.index(start):words.index(end)].replace(start, '', 1).split()
list_of_stuff 
['Dr', 'Jebediah', 'Caruseum', 'Green']

You can do anything you like with the list. For example I would parse for title like this: 

list_of_titles = ['Dr', 'Sr', 'GrandMaster', 'Pleb']
try:
    title = [i for i in list_of_stuff if i in list_of_titles][0]
except IndexError:
    #title not found, skipping
    title = ''
name = ' '.join([x for x in list_of_stuff if x != title])
print(title, name)

Upvotes: 0

Tom Wyllie
Tom Wyllie

Reputation: 2085

Sounds like a job for regular expressions. This uses the pattern (?:with)(.*?)(?:at) to look for 'with', and 'at', and lazily match anything in-between.

import re

words = 'Your meeting with Dr Green at 8pm'
start = 'with'
end = 'at'

pattern = r'(?:{})(.*?)(?:{})'.format(start, end)
match = re.search(pattern, words).group(1).strip()
print(match)

Outputs;

Dr Green

Note that the Regex does actually match the spaces on either side of Dr Green, I've included a simple match.strip() to remove trailing whitespace.

Upvotes: 3

khelili miliana
khelili miliana

Reputation: 3822

Using RE

import re
words = "Your meeting with Dr Green at 8pm"
before = "Dr"
after = "at"
result = re.search('%s(.*)%s' % (before, after), words).group(1)
print before + result

Output :

Dr Green

Upvotes: 0

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