Greetings,

I am working on a program to produce patterns. What would like is for

it to exhaustively produce all possible permutations of a sequence of

items but for each permutation produce variations, and also a sort of

stutter based on probability / weighted randomess.

Let us say we have tiles of four primary colors: ['Red', 'Blue',

'Green', 'Yellow']. Now we also have 4 alternatives or substitutes for

each color ['Maroon', 'Navy_Blue', 'Forest_Green', 'Dark_Brown']

We pick a unique permutation, say: ['Red', 'Blue', 'Yellow', 'Green']

Now I would like to pick the primary colors substitute (say 30% chance

for each element) so instead of our plain

['Red', 'Blue', 'Yellow', 'Green']

we might end up with:

['Red', 'Navy_Blue', 'Yellow', 'Forest_Green']

or

['Maroon', 'Navy_Blue', 'Yellow', 'Green']

Whatever... The main point is that sometimes the original color is

retained and sometimes the dark color is substituted.

Now I want to take this list and sometimes stutter an element so that

there is, let us say a 50% chance for each element, that it is

stuttered, and it may be repeated 1 (34%), 2(66%), or 3(33%) times. So

that we could get:

['Maroon','Maroon','Navy_Blue', 'Yellow','Yellow','Yellow','Yellow',

'Green']

The program would quit when all 24 (in the case of 4 elements) was

exhausted.

I have code that makes weighted randomness. I have code that makes

permutations, but I am having trouble putting this all together...

While i work on it though that i might ask for help... I'd like for the

code to be reusable and am building a library of functions for

patterns.

cheers,

kevin

### This is not mine, it is from a python book... I believe the Lutz

book

def permute(list):

if not list: # shuffle any

sequence

return[list] # empty

sequence

else:

res = []

for i in range(len(list)):

rest = list[:i] + list[i+1:] # delete

current node

for x in permute(rest): # permute the

others

res.append(list[i:i+1] + x) # add node at

front

return res

mport random

### This this is mine, but seems to work anyway hee hee

def windex(lst):

'''an attempt to make a random.choose() function that makes

weighted choices

accepts a list of tuples with the item and probability as a

pair

like: >>> x = [('one', 0.25), ('two', 0.25), ('three', 0.5)]

y=windex(x)'''

n = random.uniform(0, 1)

for item, weight in lst:

if n < weight:

break

n = n - weight

return item