Removing stacked control points

hit there
I switched from Vectorworks to Rhino.
Unfortunately, hatching is only possible, if there are no intersections in a curve.

I’m tried today to get a script together, with the aim to remove control points, which are stacked on top of each other.
The Data i get is usually generated automatically, so mistakes can happen and some curves have control points stacked on top of each other.

I used curve self to find the spots.

But because i’m working with multiple square kilometers, there are thousands of points to remove.
Now i’m looking for a way to remove those stacked points.

I’m greatfull for any help!

Check this command:

Rhino - RhinoScriptSyntax #curve-RemoveCurveKnot (

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Thanks for your input!
This surely will come in handy, at some point.

For my problem, this command removes the wrong points.

I’m now at the point, where I used the curve self command and the extract control point command and used set difference from the resulted points created before. Then i just interpolated the curve with a degree of 1.

Most of the data is not round anyway, but there are some part which are. With my script so far, I^m not able the have the same accuracy as the original data.

I’m now wondering, if there is a way, to delete specific control points of a curve, so that i do not have to interpolate the points, but subtract them from the original curve.

Multiple control points from a single curve stacked on top of each other is a different situation the multi-knots (multiple knots with the same parameter value). In curve with multi-knots removing the multi-knots should not reduce the number of control points, at least in the NURBS formulation used by Rhino.

Do you want to remove a specific control point, and leave the other control points in their original locations? If so in regular Rhino you simply delete the control point. In general the shape of the curve will change. Depending on the shape of the curve and the location of the control point which is deleted the change in shape may be major.

An alternative in regular Rhino is to use RemoveKnot. This will delete a control point and then adjust the location of the other control points to reduce/minimize the resulting change in shape of the curve.

Somehow the multi knots-command removes the wrong points for me.

Here you can see the curves after the command.

Maybe to explain the problem further heres a screenshot:

The red points are showing where multiple points are stacked.