Mechanical Python Result Path Plot

Question

I am working on a script to plot linearized values on a path. I've been following along with a posts on the Developer Portal, but I don't get the plot I expect. In fact, the interface plots on element faces internal to the body. I've been debugging, and I think one issue is the path's XYZ locations (via path.CoordinatesField) are not even on the structure, or where the original Path object (in the tree) is located. Any ideas?

a_austin · Answer

If I comment out line 58 from the from the script above, I get this (slightly different values because Mechanical decided to crash and I lost the code, but this at least replicates it):

So, it is recognizing something to plot on, but not what I expected. This is very weird as the field_coord coordinates input shows the correct XYZ data from the path discretization.

a_austin · Answer

Graphic of expected output on the left with Python Result plot on the right.

a_austin · Answer

Code block below…

Python
def define_dpf_workflow(analysis):

    import mech_dpf

    import Ans.DataProcessing as dpf

path = ExtAPI.DataModel.GetObjectsByName("Path")[0]

    x_0 = path.StartXCoordinate.Value

    y_0 = path.StartYCoordinate.Value

    z_0 = path.StartZCoordinate.Value

x_1 = path.EndXCoordinate.Value

    y_1 = path.EndYCoordinate.Value

    z_1 = path.EndZCoordinate.Value

path_length = ((x_1 - x_0) ** 2 + (y_1 - y_0) ** 2 + (z_1 - z_0) ** 2) ** 0.5

n_points = path.DiscretizationPoints + 2

    delta = path_length / (n_points - 1)

line_unit_vector = [(x_1 - x_0) / path_length, (y_1 - y_0) / path_length, (z_1 - z_0) / path_length]

# Line equation

    fx = lambda t: x_0 + line_unit_vector[0] * t

    fy = lambda t: y_0 + line_unit_vector[1] * t

    fz = lambda t: z_0 + line_unit_vector[2] * t

coordinates = [[fx(t * delta), fy(t * delta), fz(t * delta)] for t in range(n_points)]

    flat_coordinates = [entry for data in coordinates for entry in data]

# field_coord = dpf.FieldsFactory.Create3DVectorField(n_points)

    ## field_coord.Scoping.Ids = range(1, n_points + 1)

    #for i in range(0,n_points):

    #    field_coord.Add(i+1,coordinates[i])

field_coord = dpf.FieldsFactory.Create3DVectorField(len(coordinates))

    field_coord.Data = flat_coordinates

    field_coord.Scoping.Ids = list(range(1, len(coordinates) + 1))

ds = dpf.DataSources(analysis.ResultFileName)

    mesh_op = dpf.operators.mesh.mesh_provider()

    mesh_op.inputs.data_sources.Connect(ds)

    mesh = mesh_op.outputs.mesh.GetData()

coord_to_mesh_op = dpf.operators.mesh.points_from_coordinates(

        nodes_to_keep=field_coord.Scoping,

        mesh=mesh

    )

    path_mesh = coord_to_mesh_op.outputs.meshed_region.GetData()

ts = dpf.Scoping()

    ts.Ids = [1]

# SX

    s = dpf.operators.result.stress_X(

        requested_location="Nodal",

        data_sources=ds,

        time_scoping=ts

    )

    s2_f = s.outputs.fields_container.GetData()

mapping_operator = dpf.operators.mapping.on_coordinates(

        fields_container=s2_f,

        coordinates=field_coord,

        create_support=True,

        mesh=mesh

    )

    # fields_mapped = mapping_operator.outputs.fields_container.GetData()

# forward = dpf.operators.utility.forward_field()

    # forward.inputs.field.Connect(fields_mapped[0])

dpf_workflow = dpf.Workflow()

    # dpf_workflow.SetOutputMesh(fields_mapped[0].MeshedRegionSupport)

    dpf_workflow.SetOutputMesh(path_mesh)

    dpf_workflow.SetOutputContour(mapping_operator)

    # dpf_workflow.SetOutputChart(forward)

    dpf_workflow.Record('wf_id', True)

    this.WorkflowId = dpf_workflow.GetRecordedId()
```