How to calculate locality of modes based on the modal energy.

Ayush Kumar

I am trying to assess the locality of modes based on the modal energy.

Is it possible get all the elements that represent 90% of the total kinetic or stiffness energy of the mode and plot them? Rest of the model should be grey.

Ayush Kumar

Tested with 22R2:

Python Script:

def post_started(sender, analysis):# Do not edit this line
    define_dpf_workflow(analysis)


def define_dpf_workflow(analysis):

    import time
    from System import Array
    import mech_dpf
    import clr
    import Ans.DataProcessing as dpf
    mech_dpf.setExtAPI(ExtAPI)

    t0 = time.time()
    mode = int(this.GetCustomPropertyByPath("Info/Select Mode").ValueString)
    threshold_fraction = float(this.GetCustomPropertyByPath("Info/Threshold Fraction").ValueString)
    energy_prop = this.GetCustomPropertyByPath("Info/Select Energy").ValueString

    ds = dpf.DataSources(analysis.ResultFileName)
    model = dpf.Model(ds)
    mesh = model.Mesh

    tfs = dpf.Scoping()
    tfs.Ids = [mode]

    if energy_prop == "Kinetic Energy":
        energy = dpf.operators.result.kinetic_energy(data_sources=ds, time_scoping=tfs)
    else:
        energy = dpf.operators.result.stiffness_matrix_energy(data_sources=ds, time_scoping=tfs)
    energy_fc = energy.outputs.fields_container.GetData()

    total_energy = dpf.operators.math.accumulate_fc(fields_container=energy_fc)
    total_energy_fc = total_energy.outputs.fields_container.GetData()

    energy_sort = dpf.operators.logic.descending_sort_fc(fields_container=energy_fc)
    energy_sort_fc = energy_sort.outputs.fields_container.GetData()
    energy_sorted = energy_sort_fc[0].Data
    energy_ids = energy_sort_fc[0].Scoping.Ids

    threshold = threshold_fraction * total_energy_fc[0].Data[0]

    # Get cumulative KE
    cumulative_energy = []
    current_sum = 0
    for number in energy_sort_fc[0].Data:
        current_sum += number
        cumulative_energy.append(current_sum)

    # Get index of 90% KE
    clr.AddReference('System')

    array = Array[float](cumulative_energy)
    index = Array.BinarySearch(array, threshold)

    if index < 0:
        index = int(index * (-1.0) - 1)

    # Slice the arrays up to that index
    new_all_ke = list(energy_sorted)[:index + 1]
    new_ke_ids = list(energy_ids)[:index + 1]

    field_n = dpf.FieldsFactory.CreateScalarField(len(new_ke_ids))
    field_n.Unit = energy_sort_fc[0].Unit
    field_n.Location = energy_sort_fc[0].Location
    field_n.Scoping.Ids = new_ke_ids
    field_n.Data = new_all_ke

    field_fwd = dpf.operators.utility.forward_field(field=field_n)

    displacement = dpf.operators.result.displacement(data_sources=ds, time_scoping=tfs)

    dpf_workflow = dpf.Workflow()
    dpf_workflow.Add(displacement)
    dpf_workflow.SetOutputContour(field_fwd, dpf.enums.GFXContourType.FEElementalScoping)
    # dpf_workflow.SetOutputContour(field_fwd)
    dpf_workflow.SetOutputWarpField(displacement)
    dpf_workflow.SetOutputMesh(mesh)
    dpf_workflow.Record('wf_id', False)
    this.WorkflowId = dpf_workflow.GetRecordedId()
    t1 = time.time()
    ExtAPI.Application.LogInfo("Total time - %s" % (t1 - t0))

Property Provider code:

    mode_prop = group.AddProperty("Select Mode", Control.Options)
    res_prop = group.AddProperty("Select Energy", Control.Options)
    res_prop.Options = {1: "Kinetic Energy", 2: "Stiffness Matrix Energy"}
    threshold = group.AddProperty("Threshold Fraction", Control.Double)
    max_modes = Model.Analyses[0].AnalysisSettings.MaximumModesToFind
    mode_prop_dict = {}
    for mode in range(1, max_modes + 1):
        mode_prop_dict.update({mode: mode})
    mode_prop.Options = mode_prop_dict

Results: