Interactive plot of Matplotlib not working

[longhathuc]

Hi all,

Currently I wold like to plot interactively using Matplotlib with SOFA. Before, people told me that works. But for now, when running the plot, SOFA has to stop the animation. After closing the graph then SOFA can run again.
I don't know if this is a problem of SOFA or not? Do you have any idea? If yes, which commit should I look up to temporarily fix it?

Thanks
Long

[ateixeira0163]

I'm not sure if I understood correctly, but I'll give a try. Try adding plt.show(block=False) and plt.pause(.0001) after your plot. With this, you can plot, resume your code without closing the plot. But you cannot interact (zoom in/out) with it.

[longhathuc]

Hi, I add them but the plot is not updated when simulation run

[ateixeira0163]

How do you update your plot?
I use plt.clf() to clear and plot again from time to time with the new values.
I'm not sure if it's the best way to do it, but it gets the job done.

[longhathuc]

Before, we use this code to plot the graph. it works before. Now we have to delete plt.ion() to make the graph plot and show but have to stop the animation of SOFA. I tried plt.clf() but it results in the same.

def plotData():
    global TimeVec, PositionObjective, EntryObjective, LambdaObjective, RobotPlanObjective, RobotConfigObjective, GWindowSize;

    plt.cla()
    plt.ion()
    plt.plot(TimeVec,filter(EntryObjective,GWindowSize),'r-')
    plt.plot(TimeVec,filter(PositionObjective,GWindowSize),'g-')
    plt.plot(TimeVec,filter(LambdaObjective,GWindowSize),'b-')
    plt.plot(TimeVec,filter(RobotPlanObjective,GWindowSize),'y-')
    plt.plot(TimeVec,filter(RobotConfigObjective,GWindowSize),'k-')


    plt.title('Monitoring',fontsize=16,fontweight="bold")
    plt.ylabel('Objective function value (u.a.)',fontsize=12,color='r')
    plt.xlabel('Simulation time (s)',fontsize=12)
    plt.show()

[ateixeira0163]

I've wrote a little scene. Run this and see if it's what you want :

import Sofa
import Sofa.Gui
import SofaRuntime
import matplotlib.pyplot as plt

USE_GUI = True


def main():
    root = Sofa.Core.Node('root')
    createScene(root)
    Sofa.Simulation.init(root)
    plt.figure()

    if not USE_GUI:
        while root.getTime() < 5:  # This is done to be sure that the results will not explode
            Sofa.Simulation.animate(root, root.dt.value)
    else:
        Sofa.Gui.GUIManager.Init("myscene", "qglviewer")
        Sofa.Gui.GUIManager.createGUI(root, __file__)
        Sofa.Gui.GUIManager.SetDimension(1080, 1080)
        Sofa.Gui.GUIManager.MainLoop(root)
        Sofa.Gui.GUIManager.closeGUI()


def createScene(root):
    root.addObject('RequiredPlugin', name='SofaSparseSolver')
    root.addObject('RequiredPlugin', name='SofaDeformable')
    root.addObject('RequiredPlugin', name='SofaEngine')
    root.addObject('RequiredPlugin', name='SofaImplicitOdeSolver')
    root.addObject('RequiredPlugin', name='SofaRigid')
    root.addObject('RequiredPlugin', name='SofaSimpleFem')
    root.addObject('VisualStyle', displayFlags='showForceFields')
    root.gravity = [0, -10, 0]
    root.addObject('RegularGridTopology', name='topology', n=[3, 3, 3], min=[-1, -1, -1], max=[1, 1, 1])
    root.addObject('MeshTopology', name='mesh_topology', src='@topology')
    mech_obj = root.addObject('MechanicalObject', template='Vec3d')
    root.addObject('EulerImplicitSolver')
    root.addObject('SparseLDLSolver', template='CompressedRowSparseMatrixd')
    root.addObject('HexahedronFEMForceField', src='@mesh_topology')
    root.addObject('UniformMass', totalMass=.1)

    root.addObject(MyController(mech=mech_obj, root=root))

    return root


def update_graph(x, y):
    figure = plt.gcf()
    figure.clf()

    plt.plot(x, y)
    plt.show(block=False)
    plt.pause(.0001)


class MyController(Sofa.Core.Controller):

    def __init__(self, *args, **kwargs):
        Sofa.Core.Controller.__init__(self, *args, **kwargs)
        self.mech = kwargs['mech']
        self.root = kwargs['root']
        self.position = []
        self.time = []
        self.rate_update = 0

    def onAnimateEndEvent(self, event):
        self.position.append(self.mech.position.value[0][1])
        self.time.append(self.root.time.value)
        if self.rate_update == 100:
            update_graph(self.time, self.position)
            self.rate_update = 0
        self.rate_update += 1


if __name__ == "__main__":
    main()

Edit: If it is, I can explain if needed.

[hugtalbot]

@longhathuc does @ateixeira0163 suggestion help?

[hugtalbot]

It looks like @ateixeira0163's reply solved your question @longhathuc
If not do not hesitate to reopen a discussion

I've wrote a little scene. Run this and see if it's what you want :

import Sofa
import Sofa.Gui
import SofaRuntime
import matplotlib.pyplot as plt

USE_GUI = True


def main():
    root = Sofa.Core.Node('root')
    createScene(root)
    Sofa.Simulation.init(root)
    plt.figure()

    if not USE_GUI:
        while root.getTime() < 5:  # This is done to be sure that the results will not explode
            Sofa.Simulation.animate(root, root.dt.value)
    else:
        Sofa.Gui.GUIManager.Init("myscene", "qglviewer")
        Sofa.Gui.GUIManager.createGUI(root, __file__)
        Sofa.Gui.GUIManager.SetDimension(1080, 1080)
        Sofa.Gui.GUIManager.MainLoop(root)
        Sofa.Gui.GUIManager.closeGUI()


def createScene(root):
    root.addObject('RequiredPlugin', name='SofaSparseSolver')
    root.addObject('RequiredPlugin', name='SofaDeformable')
    root.addObject('RequiredPlugin', name='SofaEngine')
    root.addObject('RequiredPlugin', name='SofaImplicitOdeSolver')
    root.addObject('RequiredPlugin', name='SofaRigid')
    root.addObject('RequiredPlugin', name='SofaSimpleFem')
    root.addObject('VisualStyle', displayFlags='showForceFields')
    root.gravity = [0, -10, 0]
    root.addObject('RegularGridTopology', name='topology', n=[3, 3, 3], min=[-1, -1, -1], max=[1, 1, 1])
    root.addObject('MeshTopology', name='mesh_topology', src='@topology')
    mech_obj = root.addObject('MechanicalObject', template='Vec3d')
    root.addObject('EulerImplicitSolver')
    root.addObject('SparseLDLSolver', template='CompressedRowSparseMatrixd')
    root.addObject('HexahedronFEMForceField', src='@mesh_topology')
    root.addObject('UniformMass', totalMass=.1)

    root.addObject(MyController(mech=mech_obj, root=root))

    return root


def update_graph(x, y):
    figure = plt.gcf()
    figure.clf()

    plt.plot(x, y)
    plt.show(block=False)
    plt.pause(.0001)


class MyController(Sofa.Core.Controller):

    def __init__(self, *args, **kwargs):
        Sofa.Core.Controller.__init__(self, *args, **kwargs)
        self.mech = kwargs['mech']
        self.root = kwargs['root']
        self.position = []
        self.time = []
        self.rate_update = 0

    def onAnimateEndEvent(self, event):
        self.position.append(self.mech.position.value[0][1])
        self.time.append(self.root.time.value)
        if self.rate_update == 100:
            update_graph(self.time, self.position)
            self.rate_update = 0
        self.rate_update += 1


if __name__ == "__main__":
    main()

Edit: If it is, I can explain if needed.

[longhathuc]

Hi, Thank you for the answer. I have not tried it yet but hope will return to test it soon.