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[Seti <question270178@xxxxxxxxxxxxxxxxxxxxx>]

New question #270178 on Yade:
https://answers.launchpad.net/yade/+question/270178

Hi all,

I trust all is well. I am just trying to do very simple simulation( felling down grains because of their weight).

I have two questions. The first one is regarding stopping conditions : I have used the unbalancedForce to imply this condition, I do not know which is correct or not, if yes why the program does not stop of running although after several hours it seems the grains do not move.

The other question is about the text file which I have used to save the results, when I want to use it , I face with the error which is mentioned " the file you opened has some invalid characters" 

Maybe these questions are so simple to answer but I could not find the solutions. Make me glad if you help with these.

Thanks so much 

Seti

Here is the script:
#!/usr/bin/python
from yade import pack,utils#, qt
pred = pack.inAlignedBox((0,0,0),(20,200,20))
#create material
soil1 = CohFrictMat(young=1e10,poisson=0.2,frictionAngle=radians(15),density=2500.0,normalCohesion=1e6, shearCohesion=80e6,label='soil')
#color=(1,0,0) ----red color
#soil1 = FrictMat(young=1e6,poisson=0.4,frictionAngle=radians(30),density=2500.0,label='soil')
O.materials.append(soil1)
O.bodies.append(utils.wall(0,axis=1,sense=1))
O.materials.append(CohFrictMat(young=1e9,poisson=0.1, frictionAngle = radians(15) , label='wallmat'))
wallmat = O.materials[-1]

spheres=SpherePack()
spheres=pack.randomDensePack(pred,radius=1.1,material='soil',spheresInCell=1000,color=(1,0,0),returnSpherePack=True)
spheres.toSimulation()
#O.bodies.append(spheres)
#


#
O.engines=[
             ForceResetter(),#reset forces
             InsertionSortCollider([Bo1_Wall_Aabb(),Bo1_Sphere_Aabb()]),
             InteractionLoop(
                            [Ig2_Sphere_Sphere_ScGeom6D(),Ig2_Wall_Sphere_ScGeom()], # collision geometry
                            [Ip2_CohFrictMat_CohFrictMat_CohFrictPhys()], # collision "physics"
                            [Law2_ScGeom6D_CohFrictPhys_CohesionMoment(),Law2_ScGeom_FrictPhys_CundallStrack()] # contact law -- apply forces
                                            ),
                      # apply gravity force to particles
                            # damping: numerical dissipation of energy
                            NewtonIntegrator(damping=0.5,gravity=(0,-9.81,0)),
                            #qt.SnapshotEngine(fileBase='3d-',iterPeriod=200,label='snapshot'),
   # this engine will be called after 20000 steps, only once
                            #PyRunner(command='finish()',iterPeriod=20000)
]

# set timestep to a fraction of the critical timestep
# the fraction is very small, so that the simulation is not too fast
# and the motion can be observed
O.dt=1*utils.PWaveTimeStep()
#makeVideo(snapshot.snapshots,'3d.mpeg',fps=10,bps=10000)
# save the simulation, so that it can be reloaded later, for experimentation
#O.saveTmp()
def checkUnbalanced():
   if unbalancedForce()<10:
      O.pause()
#plot.saveDataTxt('modi.data.bz2')
      # plot.saveGnuplot('bbb') is also possible

# collect history of data which will be plotted
def addPlotData():
   # each item is given a names, by which it can be the unsed in plot.plots
   # the **O.energy converts dictionary-like O.energy to plot.addData arguments
   plot.addData(i=O.iter,unbalanced=unbalancedForce(),**O.energy)
O.save('Modified.data.bz2')

#O.save('confinedState'+key+'.yade.gz')
from yade import qt
qt.View()
#O.run()
#from yade import qt
#qt.View()
#O.run()
# this function is called when the simulation is finished
#def finish():
   # snapshot is label of qt.SnapshotEngine
   # the 'snapshots' attribute contains list of all saved files
   #makeVideo(snapshot.snapshots,'3d.mpeg',fps=10,bps=10000)
   #O.pause()

# set parameters of the renderer, to show network chains rather than particles
# these settings are accessible from the Controller window, on the second tab ("Display") as well
#rr=yade.qt.Renderer()
#rr.shape=False
#rr.intrPhys=True

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