maths.special_numbers.happy_number
==================================

.. py:module:: maths.special_numbers.happy_number


Functions
---------

.. autoapisummary::

   maths.special_numbers.happy_number.is_happy_number


Module Contents
---------------

.. py:function:: is_happy_number(number: int) -> bool

   A happy number is a number which eventually reaches 1 when replaced by the sum of
   the square of each digit.

   :param number: The number to check for happiness.
   :return: True if the number is a happy number, False otherwise.

   >>> is_happy_number(19)
   True
   >>> is_happy_number(2)
   False
   >>> is_happy_number(23)
   True
   >>> is_happy_number(1)
   True
   >>> is_happy_number(0)
   Traceback (most recent call last):
       ...
   ValueError: number=0 must be a positive integer
   >>> is_happy_number(-19)
   Traceback (most recent call last):
       ...
   ValueError: number=-19 must be a positive integer
   >>> is_happy_number(19.1)
   Traceback (most recent call last):
       ...
   ValueError: number=19.1 must be a positive integer
   >>> is_happy_number("happy")
   Traceback (most recent call last):
       ...
   ValueError: number='happy' must be a positive integer