yade-users team mailing list archive

[Bruno Chareyre <bruno.chareyre@xxxxxxxxxxx>]

Note : ResultantForceEngine.pro and TriaxialStressController.pro  both 
contain this line :

LIBS += -lStiffnessCounter \

In fact , it is not necessary, and it causes a problem if compiled after 
a "make clean" command has been issued, because StiffnessCounter is a 
StandaloneEngine, so it is compiled _after_ TriaxialStressController 
which is a DeusExMachina engine...

Just remove the line.

Bruno



Bruno Chareyre a écrit :

> Hello Janek
>
> I've written new classes in order to 1) control the triaxial stress in 
> a box and 2) compute an accurate critical time-step.
> Point 1. is complete and has a dedicated FileGenerator 
> ("TriaxialTest"). Point 2. is not complete but I have almost 
> everything in hands to do it now :), it should arrive soon.
>
> Everything is added in the DEM package (attached file) :
> - StiffnessMatrix added to PhysicalAction (in fact it is not a matrix, 
> it is only the vector of diagonal terms...)
> - StiffnessCounter added to StandaloneEngine to compute the Stiffness 
> matrix of bodies
> - ResultantForceEngine added to DeusExMachina (should rename to 
> ResultantForceController?...) to control the resultant force on a body.
> - TriaxialStressController added to DeusExMachina to control the 
> stress state in a collection of bodies.  TriaxialStressController work 
> on a group of 6 bodies - most probably 6 InteractingBoxes currently, 
> but why not 6 RigidWalls in the future?
> - TriaxialTest added to PreProcessor to demonstrate the use of 
> TriaxialStressController.
>
>
> While writing this classes, I have navigated a lot in Yade code, and I 
> have a lot of questions...
> I will only  write few of them now :
>
> Some of them turn around debug options and debugging, they are not 
> 100% yade related :
> 1 - It is said in the "INSTALL" that option -g may be used to generate 
> debug symbols. However there are debug flags in all *.pro files 
> (before one uses the "make_release" script...). So what happens if I 
> compile with "debug" flags in pro files but without -g option?
>
> 2 - I was never able to really debug my code. The only way of 
> debugging I found was based on including lots of cerr << "something" 
> in the code to have an idea of what happened (I forgot to 
> DeusExMachina::registerAttributes in 
> ResultantForceEngine::registerAttributes, so subscribedBodies was 
> empty...). What do you use for debug? Kdevelop? gdb in command-line 
> mode? Do you know a link to a good debugging tutorial for 
> gcc/kdevelop/gdb/* ?
>
> Compilation :
>
> 3 - I tried to compile a complete project (e.g. DEM-package) from 
> Kdevelop. It works! No problem with YADE_QMAKE_PATH as long as you 
> don't try to compile a sub-project. However, it results in compiled 
> objects that are 3 times bigger than those compiled with a "make 
> CXXFLAGS='-pthread -lpthread' " from the command line!! Do you know 
> the reason why? (debug symbols...?)
>
> Optimisation :
>
> 4 - I have make a rapid tour in cachegrind/kcachegrind, and if I 
> understand well, boost operations take a significant part of the 
> computation cost (particularly "/shared_ptr<something> sh_ptr = 
> existing_shared_ptr/" and /shared_ptr<something>~/ ). Don't you think 
> it could be a good idea to write specific parts of Yade, like 
> PersistentSAPCollider, with classical pointers? I seriously think 
> about this type of optimisations.
> More generally, I would really appreciate having your point of view on 
> where I should start if I plan to get faster computations.
>
>
> Bruno
>
> >  
>
>
> --
>
> ______________
> Chareyre Bruno
>      Maître de conférence
>      Institut National Polytechnique de Grenoble
>
>      Tél : 04.56.52.86.21
> ______________
>
>      Bureau I 08
>      Laboratoire 3S (Soils Solids Structures)
>      BP 53 - 38041, Grenoble cedex 9 - France
> ______________
>
>  


--

______________
Chareyre Bruno
     Maître de conférence
     Institut National Polytechnique de Grenoble

     Tél : 04.56.52.86.21
______________

     Bureau I 08
     Laboratoire 3S (Soils Solids Structures)
     BP 53 - 38041, Grenoble cedex 9 - France
______________