Removing all numbers form an input in Python

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Is there a way to remove all numbers in Python? like so:
user input: Lorem Ipsum 78432 Lorem Ipsum

Output: Lorem Ipsum Lorem Ipsum

I’ve tries looking it up, its only about removing spaces, I’ve also tried using .replace(‘X’, ”)

  • 1

    Of course this can be done with replace and there are several other (better) possibilities. Please show us your code that does not work and we may be able to tell you where the error lies.

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  • @Matthias There is no error, I am making a tycoon game in Python, and I recently found .replace, and I am using it to test for commands, and I will have 2 variables, one being the amount to buy, the other being the item to buy.

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  • I would recommend the re package and re.sub() specifically if you know regex at all. The pattern is dead simple if you don’t care about printing a double space now and then

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  • 1

    Like Matthias said, post just the code for this function, and we can easily say why it’s wrong, and correct it.

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  • 1

    Do you allow floating-point numbers (i.e., 1.0, 1e10), or just integers?

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You can make a list with all the characters you want to remove to the sentence, then loop through each character in the user input, and see whether its in the list of characters you want to remove. If it is not on the list, we’ll add it to a list with all the characters that we want to keep. And if the character is in the list, we’ll ignore it. Like so:

#Make a function called clean_input, which takes 1 arguement - the sentence that you want to clean
def clean_input(input):
    #make sure input is a string, in case it was only numbers
    str(input)

    #make a list of all the characters you want to remove from the sentence
    undesired_characters = ['1', '2', '3', '4', '5', '6', '7', '8', '9', '0']
    #make a list to contain the characters that aren't in the list of undesired characters
    desired_characters = []

    #loop through every character in the sentence
    for character in input:
        #if the letter isn't in the list of undesired characters
        if character not in undesired_characters:
            #append it to the list of desired characters
            desired_characters.append(character)
        #if the character is in the list of undesired characters
        elif character in undesired_characters:
            #skip it, go to the next character
            pass

    #join the characters in the list into a string, with nothing being added between
    cleaned_input = "".join(desired_characters)

    #remove any double spaces ('  ')
    cleaned_input = cleaned_input.replace("  ", " ")

    #return the cleaned up input
    return cleaned_input

#clean a sentence using our function, and print it
new_input = clean_input("Lorem Ipsum 78432 Lorem Ipsum")
print (new_input)

The output will be:

Lorem Ipsum Lorem Ipsum

PS – We need to remove double spaces because if you have hello 4 hello and you remove 4, you’ll be left with hello hello. So after removing all numbers, we check for the double spaces and replace it with a single space.

Here is solution to exclude both integer and floating-point numbers with type casting and exception handling

def not_a_type(val, type_cast_func):
    try:
        type_cast_func(val)
    except:
        return True
    return False

def not_a_number(val):
    return not_a_type(val, int) and not_a_type(val, float)

def exclude_numbers(input_str): 
    list_str = input_str.split()
    return " ".join(list(filter(not_a_number, list_str)))

my_input = "Lorem Ipsum 78432 7.8432 7842E2 784.2e2 Lorem Ipsum"
print(f"{exclude_numbers(my_input) = }")

prints

exclude_numbers(my_input) = 'Lorem Ipsum Lorem Ipsum'

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