Doctest python

"""
This is the "example" module.

The example module supplies one function, factorial().  For example,

>>> factorial(5)
120
"""

def factorial(n):
    """Return the factorial of n, an exact integer >= 0.

    >>> [factorial(n) for n in range(6)]
    [1, 1, 2, 6, 24, 120]
    >>> factorial(30)
    265252859812191058636308480000000
    >>> factorial(-1)
    Traceback (most recent call last):
        ...
    ValueError: n must be >= 0

    Factorials of floats are OK, but the float must be an exact integer:
    >>> factorial(30.1)
    Traceback (most recent call last):
        ...
    ValueError: n must be exact integer
    >>> factorial(30.0)
    265252859812191058636308480000000

    It must also not be ridiculously large:
    >>> factorial(1e100)
    Traceback (most recent call last):
        ...
    OverflowError: n too large
    """

    import math
    if not n >= 0:
        raise ValueError("n must be >= 0")
    if math.floor(n) != n:
        raise ValueError("n must be exact integer")
    if n+1 == n:  # catch a value like 1e300
        raise OverflowError("n too large")
    result = 1
    factor = 2
    while factor <= n:
        result *= factor
        factor += 1
    return result


if __name__ == "__main__":
    import doctest
    doctest.testmod()

Source: docs.python.org

Similar codes

2 votes284 views1 answer
Flask form
Python Flask
1 vote235 views2 answers
Normalize = true pandas
Python
0 vote291 views1 answer
Tadjust margines automatically matplotlib
Python
0 vote311 views1 answer
Python using string to access objects
Python
0 vote271 views1 answer
\n vs \r python
Python
0 vote271 views1 answer
Len range
Python
1 vote300 views1 answer
How to print hello world 10 times in python
Python
0 vote333 views1 answer
Unique mark boolean django model field
Python Django
6 votes265 views1 answer
Install pip on windows 10 python 3.9
Python
6 votes264 views6 answers
Python tuples
Python