Non deterministic MatchMeshEdge?

Hi there,

Here is what i think is a case of non-deterministic behaviour from the “MatchMeshEdge” command, using Rhino 7. From the joined .3dm file, I did call the “MatchMeshEdge” function 8 times, using “UP - Input” and “DOWN - Input” mesh copies as input.

McNeil_MatchMeshEdge.3dm (1.4 MB)

I put the results into “UP - Output*” and “DOWN - Output*” layers. Outputs 1-2-3-4-6-7-8 are all identical. Output #5 is different near the border. The position difference seems insignificant (about 0.017mm here) but after several other surfacing and remeshing operations, the difference between different executions of the same algorithm on same data can give differences that reach over 1.0mm

Here is the code I’ve used to produce this:

def MatchMeshEdge(meshes, DistanceToAdjust = 0.5, RatchetMode = “On”, echo=False):

cmd = "_MatchMeshEdge" 
cmd += " _DistanceToAdjust " + str(DistanceToAdjust)
cmd += " _RatchetMode="      + str(RatchetMode)
for mesh in meshes:
    cmd += " _selid " + str(mesh)
cmd += " _Enter _Enter "
rs.Command(cmd, echo=echo)

def match():
Meshes = rs.GetObjects(“Select Meshes To Match”,32)
MatchMeshEdge(Meshes, DistanceToAdjust = 0.1, echo=True)

Is there something I miss? Or a workaround to get the same result each time?

Thank you very much!