# Number validation issue

Alec Taylor alec.taylor6 at gmail.com
Fri Feb 22 16:30:49 CET 2013

```Out[1]: '0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
24 25 26 27 28 29'

In [2]: [not len(x) >= 2 and len(x)<=25 for x in _]
Out[2]: [True]*79 # shorthand to prevent spam

I trust you can see the error now!

On Sat, Feb 23, 2013 at 2:09 AM, Morten Engvoldsen <mortenengv at gmail.com> wrote:
> Hi ,
> I have wrote the below code to validate a number using modulus 10 and 11:
>
> def is_valid_number(checknum, mod):
>     if mod == 10:
>         if not len(checknum) >= 2 and len(checknum) <=25:
>             return False
>         number = tuple(int(i) for i in reversed(str(checknum)) )
>         return (sum(int(num) * 2 for num in number[1::2]) % 10) == 0
>     elif mod == 11:
>         if not len(checknum)!= 11:
>             return False
>         weights = [5, 4, 3, 2, 7, 6, 5, 4, 3, 2, 1]
>         return (sum(w * int(x) for w, x in zip(weights, checknum)) % 11) ==
> 0
>
> is_valid_number("12345678217", 10)
>
> The above code is able to validate 25 length number for modulus 10 , but for
> modulus 11 i have done the validation only for 11 digit,  Since for modulus
> 11 the weight should be in
> .............4,3,2,7,6, 5, 4, 3, 2, 7, 6, 5, 4, 3, 2, 1  in this format.
>
> Could you please let me know how can i validate the 25 length number for
> modulus 11 with weight ...............4,3,2,7,6, 5, 4, 3, 2, 7, 6, 5, 4, 3,
> 2, 1  in this format.
>
> Regards,
> Morten
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>

```