rjk Tools

Misc tools to help with programming more efficently

decorators

Example of the dynamic_programming usage on a fibonacci function

from rjk_tools.decorators import dynamic_programming

@dynamic_programming
def fib(n):
    if n == 0:
        return 0
    elif n == 1:
        return 1
    else:
        return fib(n-1) + fib(n-2)	

Example of results:

>>>fib(8)
>>>21

Without the decorator the following functioncalls would be made:

fib(8),fib(7),fib(6),fib(5),fib(4),fib(3),fib(2),fib(1),fib(0),fib(1),fib(2),fib(1),fib(0),fib(3),fib(2),fib(1),fib(0),fib(1),fib(4),fib(3),fib(2),fib(1),fib(0),fib(1),fib(2),fib(1),fib(0),fib(5),fib(4),fib(3),fib(2),fib(1),fib(0),fib(1),fib(2),fib(1),fib(0),fib(3),fib(2),fib(1),fib(0),fib(1),fib(6),fib(5),fib(4),fib(3),fib(2),fib(1),fib(0),fib(1),fib(2),fib(1),fib(0),fib(3),fib(2),fib(1),fib(0),fib(1),fib(4),fib(3),fib(2),fib(1),fib(0),fib(1),fib(2),fib(1),fib(0)

With the decorator it is reduced to:

fib(8),fib(7),fib(6),fib(5),fib(4),fib(3),fib(2),fib(1),fib(0)

Subsequent runs only run previously unrun calls.

>>>fib(9)
>>>34

The above only will run:

fib(9)