could you please help me check if any strings in a list that are next to each other have the same first letter. Im pretty new to python and my approach was to first tokenise and make the list lowercased. Then I create a nested list:
import nltk
myStrings = "Bob build a house"
myStrings_words = nltk.word_tokenize(myStrings)
myStings_words_lower = [word.lower() for word in myStrings_words]
nested_list = [list(x) for x in myStings_words_lower]
Now I'm not sure though how to compare each words 1 letter with each other and make sure that they are next to each other in the list. Maybe a for loop and accessing the 1 letters by myString_words_lower[x][1] ?
The output should be the words that have the same letter in the beginning, so in this case bob and build.
Thank you in advance, Paul
CodePudding user response：
You can use itertools.groupby to help you with this. Let's assume you have your list of lowercase words:
import nltk
myStrings = "Bob build a house"
myStrings_words = nltk.word_tokenize(myStrings)
myStings_words_lower = [word.lower() for word in myStrings_words]
To group them into any neighbours that share a first letter, you can do:
import itertools
# define a grouping helper
first_letter = lambda x: x[0]
# get the groups
grouped_words = itertools.groupby(myStings_words_lower, key=first_letter)
print(f"The number of words is {len(myStings_words_lower)} and the number of groups is {len(list(grouped_words))}")
If the number of groups is equal to the number of words, then no consecutive words share a starting letter. If the number is not equal, then you know there are neighbouring entries that share a starting letter.
CodePudding user response：
Another approach:
In [6]: myString = "Bob build an aeroplane, boat and a haunted house"
In [7]: my_words = [word.lower() for word in myString.split()]
In [8]: my_words
Out[8]: ['bob', 'build', 'an', 'aeroplane,', 'boat', 'and', 'a', 'haunted', 'house']
# Iterate over the words and while iterating, check if present word and
# the next word has the same first letter. (We use len(my_words) - 1 as
# we are using i 1 in the loop and so should stop at the penultimate word)
In [9]: for i in range(len(my_words) - 1):
...: if my_words[i][0] == my_words[i 1][0]:
...: print(my_words[i], my_words[i 1])
...:
bob build
an aeroplane,
and a
haunted house
Cheers!