CFD Online Discussion Forums - [General] python view + matplotlib: SetAttributeArrayStatus(…) for an array in vtkMultiBlockDa

One could incorporate matplotlib plots using the new type of view in paraview 4.1 called the "python view".

More details are available here.

Here is a typical script to use inside python view to plot line plots. (bar charts and cluster plots could also be made):

Code:

import vtk

def setup_data(view):

  from paraview.numpy_support import vtk_to_numpy

  for i in xrange(view.GetNumberOfVisibleDataObjects()):

    dataObject = view.GetVisibleDataObjectForSetup(i)

    view.DisableAllAttributeArrays()

    #view.EnableAllAttributeArrays()

    view.SetAttributeArrayStatus(i, vtk.vtkDataObject.POINT, "mag(wallShearStress)", 1)

    print "Done.. setup_data!"



def render(view, width, height):

  from paraview.numpy_support import vtk_to_numpy

  from paraview import python_view

  #from matplotlib import style

  #style.use('ggplot') 



  figure = python_view.matplotlib_figure(width, height)

  plt = figure.add_subplot(1,1,1)

  plt.set_xlabel('$Length \quad [m]$', fontsize=24)

  plt.set_ylabel(r'$\tau_{wall}\quad   [m/s^{2}]$  ', fontsize=24)



  for tick in plt.xaxis.get_major_ticks():

    tick.label.set_fontsize(16)

  for tick in plt.yaxis.get_major_ticks():

    tick.label.set_fontsize(16)



  for i in xrange(view.GetNumberOfVisibleDataObjects()):

    dataObject = view.GetVisibleDataObjectForRendering(i)



    tauwall = vtk_to_numpy(dataObject.GetPointData().GetArray("mag(wallShearStress)"))

    

    coord = vtk_to_numpy(dataObject.GetPoints().GetData())

    x,y,z = coord[:,0],coord[:,1],coord[:,2]

      

    plt.plot(y,tauwall,'r-', linewidth=2)

    figure.savefig('wallShear.png')

    print "Done.. render_data!"

  return python_view.figure_to_image(figure)

Here is the script to automate the whole process by saving it a "plotOverIntersection.py" and then can be executed using pvpython.

Code:

pvpython < plotOverIntersection.py

Code:





import os

try: paraview.simple

except: from paraview.simple import *

paraview.simple._DisableFirstRenderCameraReset()



script = """



import vtk

def setup_data(view):

  from paraview.numpy_support import vtk_to_numpy

  for i in xrange(view.GetNumberOfVisibleDataObjects()):

    dataObject = view.GetVisibleDataObjectForSetup(i)

    view.DisableAllAttributeArrays()

    #view.EnableAllAttributeArrays()

    view.SetAttributeArrayStatus(i, vtk.vtkDataObject.POINT, "mag(wallShearStress)", 1)

    print "Done.. setup_data!"



def render(view, width, height):

  from paraview.numpy_support import vtk_to_numpy

  from paraview import python_view

  #from matplotlib import style

  #style.use('ggplot') 



  figure = python_view.matplotlib_figure(width, height)

  plt = figure.add_subplot(1,1,1)

  plt.set_xlabel('$Length \quad [m]$', fontsize=24)

  plt.set_ylabel(r'$\tau_{wall}\quad   [m/s^{2}]$  ', fontsize=24)



  for tick in plt.xaxis.get_major_ticks():

    tick.label.set_fontsize(16)

  for tick in plt.yaxis.get_major_ticks():

    tick.label.set_fontsize(16)



  for i in xrange(view.GetNumberOfVisibleDataObjects()):

    dataObject = view.GetVisibleDataObjectForRendering(i)



    tauwall = vtk_to_numpy(dataObject.GetPointData().GetArray("mag(wallShearStress)"))

    

    coord = vtk_to_numpy(dataObject.GetPoints().GetData())

    x,y,z = coord[:,0],coord[:,1],coord[:,2]

      

    plt.plot(y,tauwall,'r-', linewidth=2)

    figure.savefig('wallShear.png')

    print "Done.. render_data!"

  return python_view.figure_to_image(figure)



"""









# create a new 'OpenFOAMReader'

case_foam = OpenFOAMReader(FileName='case.foam')   

case_foam.MeshRegions = ['wall_pipe']  #MESH REGION, USUALLY A SURFACE INCASE OF PLOTTING OVER INTERSECTION

case_foam.CellArrays = ['U', 'mag(U)', 'mag(wallShearStress)', 'p', 'wallShearStress'] # DATA TO LOAD





SetActiveSource(case_foam)





# get animation scene

animationScene1 = GetAnimationScene()



# update animation scene based on data timesteps

#animationScene1.UpdateAnimationUsingDataTimeSteps()



animationScene1.GoToLast()  #SKIP TO LAST TIME STEP





# get active view

renderView1 = GetActiveViewOrCreate('RenderView')



# Create the first P-O-L, set the extremes of the line and then commit to render

plotOnIntersectionCurves1 = PlotOnIntersectionCurves(Input=case_foam)

plotOnIntersectionCurves1.SliceType = 'Plane'



# Properties modified on plotOnIntersectionCurves1.SliceType

plotOnIntersectionCurves1.SliceType.Origin = [0, 0, 0]

plotOnIntersectionCurves1.SliceType.Normal = [1, 0, 0]



# create a new 'Merge Blocks'

mergeBlocks1 = MergeBlocks(Input=plotOnIntersectionCurves1)



view = CreateView("PythonView")

view.Script = script





Show(mergeBlocks1, view)



pythonView1 = GetActiveViewOrCreate('PythonView')

pythonView1.ViewSize = [ 1200, 1200 ]





source = mergeBlocks1

writer = CreateWriter("plotOverIntersection1.csv", source)

writer.FieldAssociation = "Points" # or "Cells"

writer.UpdatePipeline()



#SaveScreenshot('wallShear.png', magnification=2, quality=100, view=pythonView1)

#WriteImage("wallShear2.png",2)



RenderAllViews()

del writer

del plotOnIntersectionCurves1

del case_foam

Do let me know, if you need any additional details.
Cheers :-)
-Jay