I need to find a way to remove vertex groups that got a dot on their names, I tried with this code but it didnt work (well, the find part works, but it is not removing the vertex group):

for vertexname in bpy.context.object.vertex_groups:
if vertexname.name.find("\."):

ValueError: VertexGroup.remove(): error with argument 1, "index" - sequence expected at dimension 1, not 'int'

I'm not very experienced with python either, i could make that code because of my knowledge with lua, not really sure what does a sequence is in python (i was expecting it to be a table with numbers, something like [0, 1, 5, etc] but even with "vertexname.remove([0])" nothing is being removed).

  • Each item vg when iterating over object.vertex_groups is an instance of a bpy.types.VertexGroup object. (just as each of bpy.data.objects is an instance of an bpy.types.Object object)

  • Remove vg from the objects vertex group collection with ob.vertex_groups.remove(vg) A vertex group object also has a remove method, which takes a sequence of vertex indices as an argument. Eg vg.remove([0, 1]). This prob led to the confusion re error message

  • No need to escape out the period.

    >>> str("\.") 
  • If a substring is not in string then find(...) returns -1


import bpy
context = bpy.context

ob = context.object
vgs = [vg for vg in ob.vertex_groups
       if vg.name.find(".") != -1]


To make the scripts portable (copy paste jobs) I like to break down variables. Eg one edit to test with ob = context.scene.objects.get("Cube") no matter what the context object.

I favour the "while pop" method, a for vg in vgs: ob.vertex_groups.remove(vg) statement can also be used. The rationale being once an object is removed in blender, trying to re-reference it can have dire consequences... (well sometimes crash blender)

  • $\begingroup$ thank you so much for the detailed answer, your code also works awesome! thanks for the help $\endgroup$ – Shuuichi Mar 19 at 2:42

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