How to convert numbers to words without using num2word library?

I need to turn numbers from 1 - 99 into words. This is what I got so far:

num2words1 = {1: 'One', 2: 'Two', 3: 'Three', 4: 'Four', 5: 'Five', \
            6: 'Six', 7: 'Seven', 8: 'Eight', 9: 'Nine', 10: 'Ten', \
            11: 'Eleven', 12: 'Twelve', 13: 'Thirteen', 14: 'Fourteen', \
            15: 'Fifteen', 16: 'Sixteen', 17: 'Seventeen', 18: 'Eighteen', 19: 'Nineteen'}
num2words2 = ['Twenty', 'Thirty', 'Forty', 'Fifty', 'Sixty', 'Seventy', 'Eighty', 'Ninety']

def number(Number):

    if (Number > 1) or (Number < 19):
        return (num2words1[Number])
    elif (Number > 20) or (Number < 99):
        return (num2words2[Number])
    else:
        print("Number Out Of Range")
        main()

def main():
    num = eval(input("Please enter a number between 0 and 99: "))
    number(num)
main()

Now, the BIGGEST problem that I have so far is that the if, elif and else statements DO NOT seem to work. Only the first if statement runs.

The second problem is creating the string version of the numbers from 20-99....

P.S. Yes, I know about the num2word library, but I am not allowed to use it.


You can make this much simpler by using one dictionary and a try/except clause like this:

num2words = {1: 'One', 2: 'Two', 3: 'Three', 4: 'Four', 5: 'Five', \
             6: 'Six', 7: 'Seven', 8: 'Eight', 9: 'Nine', 10: 'Ten', \
            11: 'Eleven', 12: 'Twelve', 13: 'Thirteen', 14: 'Fourteen', \
            15: 'Fifteen', 16: 'Sixteen', 17: 'Seventeen', 18: 'Eighteen', \
            19: 'Nineteen', 20: 'Twenty', 30: 'Thirty', 40: 'Forty', \
            50: 'Fifty', 60: 'Sixty', 70: 'Seventy', 80: 'Eighty', \
            90: 'Ninety', 0: 'Zero'}

>>> def n2w(n):
        try:
            print num2words[n]
        except KeyError:
            try:
                print num2words[n-n%10] + num2words[n%10].lower()
            except KeyError:
                print 'Number out of range'

>>> n2w(0)
Zero
>>> n2w(13)
Thirteen        
>>> n2w(91)
Ninetyone
>>> n2w(21)
Twentyone
>>> n2w(33)
Thirtythree

Are you allowed to use other packages? This one works really well for me: Inflect. It is useful for natural language generation and has a method for turning numbers into english text.

I installed it with

$ pip install inflect

Then in your Python session

>>> import inflect
>>> p = inflect.engine()
>>> p.number_to_words(1234567)
'one million, two hundred and thirty-four thousand, five hundred and sixty-seven'

>>> p.number_to_words(22)
'twenty-two'

Your first statement logic is incorrect. Unless Number is 1 or smaller, that statement is always True; 200 is greater than 1 as well.

Use and instead, and include 1 in the acceptable values:

if (Number >= 1) and (Number <= 19):

You could use chaining as well:

if 1 <= Number <= 19:

For numbers of 20 or larger, use divmod() to get both the number of tens and the remainder:

tens, remainder = divmod(Number, 10)

Demo:

>>> divmod(42, 10)
(4, 2)

then use those values to build your number from the parts:

return num2words2[tens - 2] + '-' + num2words1[below_ten]

Don't forget to account for cases when the number is above 20 and doesn't have a remainder from the divmod operation:

return num2words2[tens - 2] + '-' + num2words1[remainder] if remainder else num2words2[tens - 2]

All put together:

def number(Number):
    if 0 <= Number <= 19:
        return num2words1[Number]
    elif 20 <= Number <= 99:
        tens, remainder = divmod(Number, 10)
        return num2words2[tens - 2] + '-' + num2words1[remainder] if remainder else num2words2[tens - 2]
    else:
        print('Number out of implemented range of numbers.')