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[Jerome Duriez <duriez@xxxxxxxxxxxxxxx>]

Hello everybody. I begin to try to use values of time step calculated by 
"GlobalStiffnessTimeStepper". But my problem is that it is always null, 
as the followings lines which are displayed on the terminal show it :
"INFO  
pkg/dem/Engine/StandAloneEngine/GlobalStiffnessTimeStepper.cpp:187 
computeTimeStep: computed timestep 0, appplied.
INFO  pkg/dem/Engine/StandAloneEngine/GlobalStiffnessTimeStepper.cpp:187 
computeTimeStep: computed timestep 9.72989e-06, BUT timestep is 0.
INFO  pkg/dem/Engine/StandAloneEngine/GlobalStiffnessTimeStepper.cpp:187 
computeTimeStep: computed timestep 9.72989e-06, BUT timestep is 0.
INFO  pkg/dem/Engine/StandAloneEngine/GlobalStiffnessTimeStepper.cpp:187 
computeTimeStep: computed timestep 9.72989e-06, BUT timestep is 0.
INFO  pkg/dem/Engine/StandAloneEngine/GlobalStiffnessTimeStepper.cpp:187 
computeTimeStep: computed timestep 9.72989e-06, BUT timestep is 0."

I began to give a look to the code and it seems to me that all that is 
normal... That is to say that it seems that at the first calculation a 
null time step was calculated and applied, and then this value was 
always kept.
I think that it is because of this line, which I have in my version 
(1311) and that some others students of my lab with older versions don't 
have :

"previousDt = min ( min(newDt , defaultDt), 1.5*previousDt );// at 
maximum, dt will be multiplied by 1.5 in one iterration, this is to 
prevent brutal switches from 0.000... to 1 in some computations "

So with a previous Dt calculated at the last iteration equal to 0, the 
new calculated value will never be applied...

So my question is (-> Bruno ?) : _did I miss the interest of this line, 
or should I modify it so that my calculations could run ??_
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