Stop condition

Hi Seti,
there might be several reasons. In your script, the unbalanced force check
is never called. Do you use the same script, or you comment/uncomment
something while running? Please next time attach exactly the same script
with which you have problem and also delete unnecessary comments (not used
commands etc., half of your script :-), it will be then more readable and
clear where the problem might be..
Thanks in advance for more information
Jan

2015-08-10 8:07 GMT+02:00 Seti <email address hidden>:

> 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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Dear Jan,

Thanks for your answer, it was right , I have fixed the first problem. :) however I have problem to save my data as txt. when I want to open the saved file , I face with the error which is mentioned " the file you opened has some invalid characters"
Would you please instruct me in this issue?

Cheers,
Seti

Here is my 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)
                             PyRunner(command='checkUnbalanced()',realPeriod=2,label='checker'),
]

# 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)

def checkUnbalanced():
   if unbalancedForce()<5e-3:
      print('Reached target , stopping')
      O.pause()

# 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('Modifiedd.txt.bz2')

#O.save('confinedState'+key+'.yade.gz')
from yade import qt
qt.View()

Hi,

I thing the file you are trying to open is a binary file. Just guessing since your extension is *.txt.bz2. Try to extract the file first.

HTH
Klaus

Hi Klaus,

Thanks for response. I have the same problem even after extracting :(

Thanks Klaus Thoeni, that solved my question.