Node numbering is inconsistent

[mikerife]

Discussed in https://github.com/ansys/pymapdl/discussions/3119

^{Originally posted by **YMDONG23** May 23, 2024} hello :) When I use the BEAM188 unit to calculate, the node number displayed in the eplot window is not the same as the node number when vtk=False. What is the reason? If you could discuss with me, thank you very much for your help！  

[germa89]

Code to replicate this issue in: https://github.com/ansys/pymapdl/discussions/3119?notification_referrer_id=NT_kwDOAa2IUbQxMDc3OTQwNTU0MToyODE0OTg0MQ#discussioncomment-9571309

GitHub

Node numbering is inconsistent · ansys pymapdl · Discussion #3119

hello :) When I use the BEAM188 unit to calculate, the node number displayed in the eplot window is not the same as the node number when vtk=False. What is the reason? If you could discuss with me,...

[germa89]

Further more, I am getting this error:

>>> mapdl.nplot(vtk=True, show_node_numbering=True)
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
Cell In[4], line 1
----> 1 mapdl.nplot(vtk=True, show_node_numbering=True)

File ~/Other_pymapdls/pymapdl_0/pymapdl/src/ansys/mapdl/core/mapdl_extended.py:1104, in _MapdlCommandExtended.nplot(self, nnum, vtk, **kwargs)
   1102         labels = [{"points": pcloud.points, "labels": pcloud["labels"]}]
   1103     points = [{"points": self.mesh.nodes}]
-> 1104     return general_plotter([], points, labels, mapdl=self, **kwargs)
   1106 # otherwise, use the built-in nplot
   1107 if isinstance(nnum, bool):

TypeError: general_plotter() got an unexpected keyword argument 'show_node_numbering'

[germa89]

I think the error comes when plotting the labels. The node IDs seems correct.

[brunotessaro]

This issue seems to happen not only on element numbering, but with general geometrical entities. Here is a minimal example creating 3 keypoints and connecting the first two with a line:

from ansys.mapdl.core import launch_mapdl

# Launch MAPDL instance
mapdl = launch_mapdl()

# Enter pre-processing mode
mapdl.prep7()

# Create keypoints 3 keypoints
mapdl.k(1, 0, 0, 0)
mapdl.k(2, 1, 0, 0)
mapdl.k(3, 1, 1, 0)

# Create line connecting keypoints 1 and 2
mapdl.l(1, 2)

# Plot the geometry
mapdl.lplot(show_line_numbering=False, show_keypoint_numbering=True, color_lines=True)

The output shows keypoint 1 connected to keypoint 3 instead of 2:

This is an import issue, specially when setting boundary conditions and/or mesh refinement over complex geometries.