Change sphere material for specific number of iterations and then restore previous one

Hi
I am not sure tu really understand... you can just do the following:

1/ Run simulation for 1000 iterations,
2/ change materials properties and contact physics (in agreement with material properties)
3/ Run simulation for 50 iterations,
4/ change materials properties and contact physics (in agreement with material properties)
5/ Run simulation for 1000 iterations,

Best,
Luc

Hi Veljko,

Luc's answer in python words

O.run(1000,True)
changeMaterial()
O.run(50,True)
changeMaterialBack()
O.run(1000,True)

you cold also do it in cycles:

for c in range(20):
    O.run(1000,True)
    changeMaterial()
    O.run(50)
    changeMaterialBack

also be careful with specific implementation of changeMaterial (yes/no
deleting interactions as changing particle material has no effect on
existing interactions and so on)

cheers
Jan

2015-04-22 16:16 GMT+02:00 Luc Sibille <<email address hidden>
>:

> Question #265693 on Yade changed:
> https://answers.launchpad.net/yade/+question/265693
>
> Status: Open => Answered
>
> Luc Sibille proposed the following answer:
> Hi
> I am not sure tu really understand... you can just do the following:
>
> 1/ Run simulation for 1000 iterations,
> 2/ change materials properties and contact physics (in agreement with
> material properties)
> 3/ Run simulation for 50 iterations,
> 4/ change materials properties and contact physics (in agreement with
> material properties)
> 5/ Run simulation for 1000 iterations,
>
> Best,
> Luc
>
> --
> You received this question notification because you are a member of
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Thanks for your answers,
could it be done using pyRunner somehow? To call function changeMaterial(), run for 50 iters, call changeMaterialBack() and continue untill pyRunner calls function again.
I forgot to mention that I used similar approach, but my problem is that I don’t know for how long my simulation is going to run, since I need to iterate until stop criterion isn’t met.

>
>
> could it be done using pyRunner somehow? To call function
> changeMaterial(), run for 50 iters, call changeMaterialBack() and continue
> untill pyRunner calls function again.
>

sure:

def changeMaterial():
   if O.iter % 1050 != 1000: return # do nothing at wrong iterations
   ...

def changeMaterialBack():
   if O.iter % 1050 != 0: return # do nothing at wrong iterations
   ...

O.engines = [
   ...
   PyRunner(iterPeriod=1,command="changeMaterial()", # iterPeriod is 1, but
the function itself determine if something needs to be done
   PyRunner(iterPeriod=1,command="changeMaterialBack()", # iterPeriod is 1,
but the function itself determine if something needs to be done
   ...
]

> I forgot to mention that I used similar approach, but my problem is that I
> don’t know for how long my simulation is going to run, since I need to
> iterate until stop criterion isn’t met.
>

instead for loop you can use while loop:

while not someStopCondition():
   O.run(1000,True)
   changeMaterial()
   O.run(50,True)
   changeMaterialBack()

cheers
Jan

Jan,
thank you for this answer. At first I tried to avoid calling pyrunner for each iteration, but in this manner it doesn't slow simulation much.