String formatting (%)

[A. Lloyd Flanagan]

pascal.parent at free.fr (Pascal) wrote in message news:<e567c03a.0404280035.79d0d973 at posting.google.com>...
> Hello,
> I've a float number 123456789.01 and, I'de like to format it like this
> "123 456 789.01".
> Is this possible with % character?

No, but this works with integers.  Not sure how it compares to the
other approaches mentioned.  You could adapt it to do floats by
stopping at the decimal point:

def addCommas(aNumber):
    if len(aNumber) < 4: return aNumber
    #how many digits before first ,?
    prefix = len(aNumber) % 3
    #need special case if digits is multiple of 3
    if prefix == 0: prefix = 3
    result = [aNumber[:prefix]]
    for a in range(len(aNumber) / 3):
        #get next 'segment' of three digits
        segment = aNumber[prefix + 3*a: prefix + 3*a + 3]
        if segment:  #can be '' if len(aNumber) divisible by 3
            result.append(segment)
    return ','.join(result)

I'm sure this can be improved.