Identify strings while removing substrings in python

Question

I have a dictionary of words with their frequencies as follows.

mydictionary = {\'yummy tim tam\':3, \'milk\':2, \'chocolates\':5, \'biscuit pudding\':3, \'sugar         


        

Answer 1

You can update your code with regex word boundary:

mydictionary = {'yummy tim tam':3, 'milk':2, 'chocolates':5, 'biscuit pudding':3, 'sugar':2}
recipes_book = "For today's lesson we will show you how to make biscuit pudding using yummy tim tam milk and rawsugar"
searcher = re.compile(r'{}'.format("|".join(map(lambda x: r'\b{}\b'.format(x), mydictionary.keys()))), flags=re.I | re.S)

for match in searcher.findall(recipes_book):
    print(match)

Output:

biscuit pudding
yummy tim tam
milk

Answer 2

One more way using re.escape. More info regarding re.escape here !!!

import re

mydictionary = {'yummy tim tam':3, 'milk':2, 'chocolates':5, 'biscuit pudding':3, 'sugar':2}
recipes_book = "For today's lesson we will show you how to make biscuit pudding using yummy tim tam milk and rawsugar"

val_list = []

for i in mydictionary.keys():
    tmp_list = []
    regex_tmp = r'\b'+re.escape(str(i))+r'\b'
    tmp_list = re.findall(regex_tmp,recipes_book)
    val_list.extend(tmp_list)

print val_list

Output:

"C:\Program Files (x86)\Python27\python.exe" C:/Users/punddin/PycharmProjects/demo/demo.py
['yummy tim tam', 'biscuit pudding', 'milk']

Answer 3

Use word boundary '\b'. In simple words

recipes_book = "For todays lesson we will show you how to make biscuit pudding using 
yummy tim tam milk and rawsugar"

>>> re.findall(r'(?is)(\bchocolates\b|\bbiscuit pudding\b|\bsugar\b|\byummy tim tam\b|\bmilk\b)',recipes_book)
['biscuit pudding', 'yummy tim tam', 'milk']