mfem
Basic example from readme not working
When trying to execute the example shown in the readme, I get the following error:
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
Cell In[5], [line 61](vscode-notebook-cell:?execution_count=5&line=61)
58 import matplotlib.pyplot as plt
59 import matplotlib.tri as tri
---> 61 triang = tri.Triangulation(verts[:,0], verts[:,1])
63 fig, ax = plt.subplots()
64 ax.set_aspect('equal')
TypeError: tuple indices must be integers or slices, not tuple
My versions:
- Python: 3.12.3
- PyMFEM: 4.8.0.1
- Matplotlib: 3.10.1
The problem: mesh.GetVertexArray() returns a tuple of 1D numpy arrays instead of a 2D numpy array. Thats why slicing [:, 0] does not work.
The example runs when replacing verts = mesh.GetVertexArray() with verts = np.array(mesh.GetVertexArray()). However, I think this should be considered only a hotfix, because the documentation states that it should return a 2D numpy array.
@jherkenhoff Thank you for reminding this. I think the reason behind this is that the vertices data is not simple contiguous array data in MFEM, and it is nice to return an numpy array as a view to the original data (thus you can modify it if you need.). I will update the doc and example.
