# stdnum.us.rtn

RTN (Routing transport number).

The routing transport number is a nine digit number used in the US banking system for processing deposits between banks.

The last digit is a checksum.

    >>> calc_check_digit('11100002')
    '5'
    >>> validate('111000025')
    '111000025'
    >>> validate('11100002')  # Not nine digits
    Traceback (most recent call last):
        ...
    InvalidLength: ..
    >>> validate('11100002B')  # Not all numeric
    Traceback (most recent call last):
        ...
    InvalidFormat: ..
    >>> validate('112000025')  # bad checksum
    Traceback (most recent call last):
        ...
    InvalidChecksum: ..

`stdnum.us.rtn.``calc_check_digit`(number)

  Calculate the check digit. The number passed should not have the check digit included.

`stdnum.us.rtn.``compact`(number)

  Convert the number to the minimal representation. This strips the number of any surrounding whitespace.

`stdnum.us.rtn.``is_valid`(number)

  Check if the number is a valid RTN.

`stdnum.us.rtn.``validate`(number)

  Check if the number is a valid routing number. This checks the length and check digit.