what to do when index is out of range when checking last index number?

user_13936417 0
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Hello I'm new at python and I'm writing a module which should take a string as input and the output should be a list of each word, number or symbol with no white spaces. i.e (' 10 sweet apples') --> ['ten', 'sweet', 'apples']. To do so I have a start value which marks the current index number and a end value which increments as long as the next thing in the string is a letter or digit. So far I've successfully added words, numbers, symbols ect to a list which is to be returned at the end of the for loop.

my problem occurs when I'm at the last index number. I have this code :

def tokenize (lines):
    tokenizedList = []
    for line in lines:
        endValue = 0
        startValue = 0
        while startValue < len(line):   

            if line[endValue].isalpha():
                while line[endValue].isalpha():
                    endValue = endValue + 1
                word = line[startValue : endValue]
                tokenizedList.append(word)
                startValue = endValue
                
            elif line[endValue].isdigit():
                while line[endValue].isdigit():
                    endValue = endValue + 1
                word = line[startValue : endValue]
                tokenizedList.append(word)
                startValue = endValue
            
            elif line[endValue].isspace():
                while line[endValue].isspace():
                    startValue += 1
                    endValue = startValue
            
            else:
                endValue += 1
                word = line[startValue : endValue]
                tokenizedList.append(word)
                startValue = endValue
    
        return tokenizedList

since the while loops in the if-statements increments endValue, it will eventually be out of range of the index. I can't figure out how to stop this error from occuring and how the while loop should be altered so it knows when to stop checking for the last letter. Any ideas?

indexoutofrangeexception while-loop list python
1 Answers

You could simply use the built in split method:

tokenizedList = ' my 3 words'.split(' ')

returns ['my', '3', 'words']

However, if you want to stick to your code, you could add another condition before you increase endValue:

if line[endValue].isalpha():
    while line[endValue].isalpha() and endValue < len(line)-1:
        endValue += 1
    word = line[startValue : endValue]

Don't forget to change the code for the digits accordingly.

user_72681210
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