How can I generate python results for every time step?

M

An excellent question.
If you have a model with multiple time steps you can use a python code object to grab the time and create a unique python result.

The python code object script example below will get the time steps:

    #analysis = ExtAPI.DataModel.Project.Model.Analyses[0]
    steps = analysis.AnalysisSettings.NumberOfSteps
    solution = analysis.Solution

and if you have a pre prepared text for a python result:

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

def define_dpf_workflow(analysis):
    step = float({step})
    import mech_dpf
    import Ans.DataProcessing as dpf
    mech_dpf.setExtAPI(ExtAPI)
    dataSource = dpf.DataSources(analysis.ResultFileName)
    u = dpf.operators.result.displacement()
    nrm = dpf.operators.math.norm_fc()

    u.inputs.data_sources.Connect(dataSource)
    nrm.Connect(u)

    scale_op = dpf.operators.math.scale()
    scale_value = float(step)
    scale_op.inputs.ponderation.Connect(scale_value)
    scale_op.inputs.field.Connect(nrm)

    dpf_workflow = dpf.Workflow()
    dpf_workflow.Add(u)
    dpf_workflow.Add(nrm)
    dpf_workflow.SetInputName(u, 0, 'time')
    dpf_workflow.Connect('time', step)
    dpf_workflow.SetOutputContour(scale_op)
    dpf_workflow.Record('wf_id', False)
    this.WorkflowId = dpf_workflow.GetRecordedId()
"""

You can loop through the time steps to use the myPR text to a series of python results and append (using .format()) any required changes to the python result you need. Here I just set a parameter, step, and that is used in the script below to set the time of the result and a scaling factor.

Note the weird indentation in the triple quoted text. That is required to get it to format properly in the python result.

    for step in range(steps):
        print(step)
        pr = solution.AddPythonResult()
        pr.Name = 'def_step_' + str(step)
        pr.Text = myPR.format(step=step)
        pr.Connect()
        pr.ReloadProperties()
solution.EvaluateAllResults()

The .format command can of course be used to add more than one value into the python result text. Just put the name parameter={parameter} in the curly brackets and add another parameter to the format statement at the end .format(step=step,parameter=parameter) when you write it to the python result.

You can adapt this in an After Solve Python Code Object and it should generate a python result with the time step variable as a scale parameter in each.

Mike.Thompson

Also keep in mind python results can handle time history data in a single object. Pulling results with DPF typically yields a fields container that has the time points (each set a field in the container). You can modify the field data while in the container and leave as a single object, which is the more typical approach.