Design Script - Imperative kmeans

After the Dynamo teams persentation today on design script I got energized and dove back into Dynamo’s Imperative functions. I have had the goal for a few years to get Kmean to work in Design script with no luck. I got a bit closer today but still confused and not even sure if it is even possible.

Attached is the .dyn with the required function. How to inbed them into a while loop is the question?!?

Kmean (Python) explanation : CS221

Kmeans.dyn (54.0 KB)


Good persentation today, thanks for the inspration!


Great with your descriptions in dynamo .

Replication guides don’t work within Imperative blocks.
You could however create an associative function that does the needful and call it within the imperative block

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See if this is adequate. Not complete though.

Kmeans-20210910-1.dyn (24.7 KB)

// Group by Centroid
def k1(pnts:var[]..[],cnts:var[]..[])
	lbl1 = "A"..#(List.Count(cnts))..1;

	//Distance to Centroids
	dst1 = pnts<1>.DistanceTo(cnts<2>);
	dst2 = List.SortByKey(lbl1,dst1<1>);
	dst3 = List.FirstItem(dst2["sortedList"]<1>);

	//Group by Closest to Centroid
	pnt1 = List.GroupByKey(pnts,dst3)["groups"];
	return pnt1;

// Centroid
def ctr (pnts:var[]..[])
	return Point.ByCoordinates(Math.Average(pnts.X),

// K Mean
def kMean (pnts:var[]..[],k:int)
	pnt1 = k1(pnts,pnts[1..k]);
	cnt1 = 1;
	pnt2 = [];
	pts1 = [Imperative]
		while (cnt1 <= k)
			ctr1 = ctr(pnt1);
			pnt2 = k1(List.Flatten(pnt1,-1),ctr1);
			cnt1 = cnt1 + 1;
			pnt1 = pnt2;
		return pnt2;
	return pts1;

Thanks @Vikram_Subbaiah!! What version of Dynamo did you use?
I open your script using Dynamo 2.6.1 and got one large cluster. I’ll be taking a closer look this weekend.

Dose this function make the Centroids?

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Try this new look daily build
I’ve used a csv file (change attached txt extension to csv) instead of Remember
Kmeans-20210910-2.dyn (16.0 KB)
pnts.txt (218.9 KB)




Looks fancy the new look…:wink: does it comes with next update for revit as well??