Dump mesh into a XDMF file

This small example shows how to dump a mesh and fields into a XDMF file that can be read by ParaView.

from BasicTools.Containers import UnstructuredMesh
from BasicTools.IO.XdmfWriter import WriteMeshToXdmf
from BasicTools.Containers import UnstructuredMeshCreationTools as UMCT
from scipy.spatial import Delaunay
import numpy as np

def create_mesh_example() -> UnstructuredMesh:
    """This function creates a dummy mesh using Delaunay triangulation.
    """
    # Create a grid of points
    x, y = np.meshgrid(np.linspace(0,1,10), np.linspace(0,1,10))
    points = np.stack([x.ravel(), y.ravel()], axis=1)
    # Generate the triangles with Delaunay
    tri = Delaunay(points)
    triangles = tri.simplices
    # Create a BasicTools UnstructuredMesh using the CreateMeshOfTriangles utility
    mesh = UMCT.CreateMeshOfTriangles(points, triangles)
    return mesh

if __name__ == "__main__":

    # Create a simple mesh
    mesh = create_mesh_example()
    
    # Make six dummy nodal fields
    fields = np.random.randn(mesh.GetNumberOfNodes(), 6)
    
    # Dump the mesh and nodal fields into a XDMF file
    WriteMeshToXdmf(filename="WriteXdmf.xdmf",                          # path where the file will be stored
                    baseMeshObject=mesh,                                # UnstructuredMesh object 
                    PointFields=[fields[:,i] for i in range(6)],        # list of scalar fields
                    PointFieldsNames=[f"field_{i}" for i in range(6)],  # list of names for each scalar field
    )