Hi dear community,
I would like to find all the possible “permutations” in a grid which look like this (see piece attachee)
I would like also to have 2 colors instead of the “X” and the “Y”, could you help me to write the good definition ?
Thank you very much in advance
You have only two items really, “XY” and “YX”. How about a product with repeat set to 5.
In the following example repeat set to 3.
import itertools
l = ("XY", "YX")
for p in itertools.product(l, repeat=3):
for n in p:
print n
print "-" * 20
This gives as output
XY
XY
XY
--------------------
XY
XY
YX
--------------------
XY
YX
XY
--------------------
XY
YX
YX
--------------------
YX
XY
XY
--------------------
YX
XY
YX
--------------------
YX
YX
XY
--------------------
YX
YX
YX
--------------------
Is that what you are looking for?
Thank you very much, I was more looking for a grasshopper definition eheh, but thank you for the idea… I will try to find an application with grasshopper rhino
You can use Nathan’s script in Grasshopper by making it into a custom component:
I’ve modified it slightly to integrate it better.
permutations.gh (3.9 KB)
For a purely GH approach, it sound like you are looking for something like Cross Reference (CrossRef).
Thank you very much for your grasshopper approach its much more explicit to me (sorry not a great mathematic background!), In fact I’m looking for all the possible permutation of X and Y (with 50 perrcent of X and 50 percent of Y) In grids like this… I would like to know how many combinaisons are possible…
Theophile, I don’t mean to be rude, but that’s literally what both Nathan and me already showed you.
You probably should have taken a closer look and experimented a little yourself, since that’s really what learning is about.
There seem to be 5120 permutations for what you’ve sketched above!
I strongly suggest you take another look.
permutations-2.gh (6.2 KB)
Ok sorry about that, It seems that I have not enough maths/grasshopper skills to use your definition in this case ^^ sorry about that !
I don’t need all the possible permutations between XY I would like only the permutations with 50% of X and 50% of Y in the same grid… I’m sorry if I’m not so clear :S like in the following drawing…
There are less more possible permutations in this case…
Thank you in advance for your patience…
How to apply this “rule” / constraint" of 50% of X and 50% of Y to your definition
Here on for this particular setup, slight adaptation of the definition posted by @diff-arch
permutations-2_jK.gh (8.9 KB)
ghenv.Component.Name = "Pythonic Cartesian Product"
ghenv.Component.NickName = "CProd"
from ghpythonlib import treehelpers
import itertools
def satisfy_50(I,l):
s = "".join(l)
c = s.count(I[0])
if c == 0:
return False
return (len(s) / c) == 2
if __name__ == "__main__":
product_one = ["".join(p) for p in itertools.product(I, repeat=2)]
all_permutations = [list(p) for p in itertools.product(product_one, repeat=R)]
permutations = [p for p in all_permutations if satisfy_50(I, p)]
P = treehelpers.list_to_tree(permutations)
AP = treehelpers.list_to_tree(all_permutations)
It sounds amazing! 
Hi again dear community,
Do you have any idea of the best way to transpose visually this approach ?
I mean the best would be to have instead of the X and the Y some colors or pictures in tables (like in my following drawing in the piece attachee) how would you proceed to achieve that ?
Thank you very Much
Hi Nathan!
I think I missed something or maybe there is a mistake in your permutation script, @nathanletwory, because for example I can’t find the following permutations (see attachee) in the results that is given by your pythonic cartesian product… It would means that there are not all the possible permutations between X and Y (with the constraint of 50% of X and 50% of Y) with this approach of the cartesian product !?
Do you have an idea ?
Cheers and thank you very much for your Help…
Thank you very much for your feedback, I tcheck that 
Here a small update to the script so that it is easier to check if a certain pattern exists
permutations-2_jK__itemindex.gh (14.0 KB)
@nathanletwory @diff-arch @Adam_ Everything works great amazing
I achieved what I was trying to achieve thanks to you !
Good fortunes in your projects with Rhino and Grasshopper!
