Is there a way to convert number words to Integers?

Question

I need to convert one into 1, two into 2 and so on.

Is there a way to do this with a library or a class or anythi

Answer 1

I needed something a bit different since my input is from a speech-to-text conversion and the solution is not always to sum the numbers. For example, "my zipcode is one two three four five" should not convert to "my zipcode is 15".

I took Andrew's answer and tweaked it to handle a few other cases people highlighted as errors, and also added support for examples like the zipcode one I mentioned above. Some basic test cases are shown below, but I'm sure there is still room for improvement.

def is_number(x):
    if type(x) == str:
        x = x.replace(',', '')
    try:
        float(x)
    except:
        return False
    return True

def text2int (textnum, numwords={}):
    units = [
        'zero', 'one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight',
        'nine', 'ten', 'eleven', 'twelve', 'thirteen', 'fourteen', 'fifteen',
        'sixteen', 'seventeen', 'eighteen', 'nineteen',
    ]
    tens = ['', '', 'twenty', 'thirty', 'forty', 'fifty', 'sixty', 'seventy', 'eighty', 'ninety']
    scales = ['hundred', 'thousand', 'million', 'billion', 'trillion']
    ordinal_words = {'first':1, 'second':2, 'third':3, 'fifth':5, 'eighth':8, 'ninth':9, 'twelfth':12}
    ordinal_endings = [('ieth', 'y'), ('th', '')]

    if not numwords:
        numwords['and'] = (1, 0)
        for idx, word in enumerate(units): numwords[word] = (1, idx)
        for idx, word in enumerate(tens): numwords[word] = (1, idx * 10)
        for idx, word in enumerate(scales): numwords[word] = (10 ** (idx * 3 or 2), 0)

    textnum = textnum.replace('-', ' ')

    current = result = 0
    curstring = ''
    onnumber = False
    lastunit = False
    lastscale = False

    def is_numword(x):
        if is_number(x):
            return True
        if word in numwords:
            return True
        return False

    def from_numword(x):
        if is_number(x):
            scale = 0
            increment = int(x.replace(',', ''))
            return scale, increment
        return numwords[x]

    for word in textnum.split():
        if word in ordinal_words:
            scale, increment = (1, ordinal_words[word])
            current = current * scale + increment
            if scale > 100:
                result += current
                current = 0
            onnumber = True
            lastunit = False
            lastscale = False
        else:
            for ending, replacement in ordinal_endings:
                if word.endswith(ending):
                    word = "%s%s" % (word[:-len(ending)], replacement)

            if (not is_numword(word)) or (word == 'and' and not lastscale):
                if onnumber:
                    # Flush the current number we are building
                    curstring += repr(result + current) + " "
                curstring += word + " "
                result = current = 0
                onnumber = False
                lastunit = False
                lastscale = False
            else:
                scale, increment = from_numword(word)
                onnumber = True

                if lastunit and (word not in scales):                                                                                                                                                                                                                                         
                    # Assume this is part of a string of individual numbers to                                                                                                                                                                                                                
                    # be flushed, such as a zipcode "one two three four five"                                                                                                                                                                                                                 
                    curstring += repr(result + current)                                                                                                                                                                                                                                       
                    result = current = 0                                                                                                                                                                                                                                                      

                if scale > 1:                                                                                                                                                                                                                                                                 
                    current = max(1, current)                                                                                                                                                                                                                                                 

                current = current * scale + increment                                                                                                                                                                                                                                         
                if scale > 100:                                                                                                                                                                                                                                                               
                    result += current                                                                                                                                                                                                                                                         
                    current = 0                                                                                                                                                                                                                                                               

                lastscale = False                                                                                                                                                                                                              
                lastunit = False                                                                                                                                                
                if word in scales:                                                                                                                                                                                                             
                    lastscale = True                                                                                                                                                                                                         
                elif word in units:                                                                                                                                                                                                             
                    lastunit = True

    if onnumber:
        curstring += repr(result + current)

    return curstring

Some tests...

one two three -> 123
three forty five -> 345
three and forty five -> 3 and 45
three hundred and forty five -> 345
three hundred -> 300
twenty five hundred -> 2500
three thousand and six -> 3006
three thousand six -> 3006
nineteenth -> 19
twentieth -> 20
first -> 1
my zip is one two three four five -> my zip is 12345
nineteen ninety six -> 1996
fifty-seventh -> 57
one million -> 1000000
first hundred -> 100
I will buy the first thousand -> I will buy the 1000  # probably should leave ordinal in the string
thousand -> 1000
hundred and six -> 106
1 million -> 1000000