Search found 32 matches

by frankst
Tue 04 Jul 2017, 09:00
Forum: Usage
Topic: Cylindrical Coordinate System
Replies: 4
Views: 4514

Re: Cylindrical Coordinate System

Hi all, - should primitives be defined in the [-pi;pi] or [0 2pi] range or does it wrap around? It should not matter at all. You could even go from 4*pi to 6*pi or anything else. Using Cartesian coordinates, I have seen cases where this did matter. Adding elements with AddRotPoly or AddBox (with "Co...
by frankst
Fri 30 Jun 2017, 09:44
Forum: Development
Topic: Possible speed optimization for PEC?
Replies: 15
Views: 12768

Re: Possible speed optimization for PEC?

Hi Thorsten, Indeed, I am talking about the SSE engine. I am looking at https://github.com/thliebig/openEMS/blob/master/FDTD/engine_sse_compressed.cpp Despite looking simpler, https://github.com/thliebig/openEMS/blob/master/FDTD/engine_sse.cpp doesn't improve my understanding. Surely, https://github...
by frankst
Thu 29 Jun 2017, 12:15
Forum: Development
Topic: Possible speed optimization for PEC?
Replies: 15
Views: 12768

Re: Possible speed optimization for PEC?

Hi Thorsten, I get the idea of the pos=0 treatment for x and y. But for z you do it totally different. It seems in z direction you first loop and then mix first cell (pos[2]=0) and last cell (pos[2]=numVectors-1). Even more confusing, UpdateVoltages and UpdateCurrents loop differently over pos[2]. C...
by frankst
Wed 28 Jun 2017, 09:11
Forum: Development
Topic: Possible speed optimization for PEC?
Replies: 15
Views: 12768

Re: Possible speed optimization for PEC?

Hi Thorsten, I am slightly surprised that you just use floats. Double precision is not required? It seems for multi-threading you cut the mesh in x direction only. That means, every thread cycles over part of the x mesh but the full y and z meshes. Right? Why do you need the extra treatment of pos[2...
by frankst
Tue 27 Jun 2017, 12:31
Forum: Development
Topic: Possible speed optimization for PEC?
Replies: 15
Views: 12768

Re: Possible speed optimization for PEC?

Hi Thorsten, I had a look at the code. If I understand your engines correctly, in UpdateVoltages and UpdateCurrents you have three nested for loops cycling over the grid. You use "pos" for the three indices to get the correct cell within the 3d mesh. Correct? But what is "shift" in UpdateVoltages? F...
by frankst
Tue 27 Jun 2017, 09:07
Forum: Feedback
Topic: Typo in AutoSmoothMeshLines.m
Replies: 2
Views: 3980

Re: Typo in AutoSmoothMeshLines.m

Hi Thorsten,

I fixed some more single quote typos in AutoSmoothMeshLines.m which prevented warnings from showing correctly (on Win10 with Octave 4.2.0).
My edited version is attached.

Cheers
Frank
by frankst
Tue 20 Jun 2017, 09:32
Forum: Development
Topic: Possible speed optimization for PEC?
Replies: 15
Views: 12768

Re: Possible speed optimization for PEC?

Hi Thorsten,

Thank you for the explanations and for pointing out where to look in the code.

Cheers
Frank
by frankst
Fri 16 Jun 2017, 09:36
Forum: Development
Topic: Possible speed optimization for PEC?
Replies: 15
Views: 12768

Re: Possible speed optimization for PEC?

Hi Thorsten, Since I have to cut out structures of different sizes from a block of PEC, I end up having a lot PEC within the meshed region. Certainly, I would prefer not to waste my mesh for PEC, but I haven't found a better solution. Of course, an "if" is required that checks for a flag. This flag ...
by frankst
Fri 16 Jun 2017, 08:44
Forum: Development
Topic: Possible speed optimization for PEC?
Replies: 15
Views: 12768

Re: Possible speed optimization for PEC?

Hi Thorsten, I hope I understand your answer correctly ;-) I agree that an extra "if" would add to the computation time. But I wonder if skipping PEC cells should not reduce the amount of data that has to be read and written to the memory. And since memory bandwidth is the limit (not CPU speed), I w...
by frankst
Thu 15 Jun 2017, 14:32
Forum: Development
Topic: Possible speed optimization for PEC?
Replies: 15
Views: 12768

Possible speed optimization for PEC?

Hi Thorsten, Is it possible that openEMS always calculates fields for all cells, even the ones which are a priori known to be field free, e.g. cells within PEC? Wouldn't it be possible to exclude such cells from calculation? For example, during setup phase PEC cells which are fully surrounded by oth...