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  • Mar 11 2019 15:01

    craig-warren on master

    Update to default GPU device ID. (compare)

  • Mar 11 2019 15:00

    craig-warren on master

    Update to handle no GPU device … (compare)

  • Mar 11 2019 14:57

    craig-warren on master

    Updates to GPU detection. (compare)

  • Mar 11 2019 14:55

    craig-warren on master

    Updates to GPU detection. (compare)

  • Mar 11 2019 14:30

    craig-warren on master

    Updated method for detecting av… (compare)

  • Mar 11 2019 14:00

    craig-warren on master

    Work on MPI spawning with GPU s… (compare)

  • Mar 08 2019 17:09

    craig-warren on master

    Update info on GPU command line… (compare)

  • Mar 08 2019 16:58

    craig-warren on master

    Updated lookup of CUDA devices. (compare)

  • Mar 08 2019 16:07

    craig-warren on master

    Modifications to GPU detection. (compare)

  • Mar 08 2019 10:41

    craig-warren on master

    Further MPI messages updates. (compare)

  • Mar 08 2019 10:26

    craig-warren on master

    Update MPI messages. (compare)

  • Mar 08 2019 09:02
    zirlman commented on 17a48f6
  • Mar 08 2019 08:59

    craig-warren on master

    Updated MPI messages. (compare)

  • Mar 08 2019 08:54

    craig-warren on master

    Updated dispersion warnings to … (compare)

  • Mar 07 2019 17:46
    zirlman edited #192
  • Mar 07 2019 17:46
    zirlman edited #192
  • Mar 07 2019 17:46
    zirlman opened #192
  • Mar 07 2019 16:43

    craig-warren on master

    Print message defaults to True. (compare)

  • Mar 07 2019 16:42

    craig-warren on master

    Clean up flags for printing mes… (compare)

  • Mar 07 2019 14:39

    craig-warren on master

    Added additional skill to proje… (compare)

Ali Shirvani
@alishir
Hi, I'm new to gprMax, I want to simulate magnetic field around a simple solenoid, would you please guide me? Where should I start and how should I proceed?
Antonis Giannopoulos
@agianno
@alishir Hi Ali, FDTD which gprMax is based on might not be the best method for simulating such problems. Try to find an example similar to your problem and see what methods other people have used to simulate this. FDTD is primarily good for transient wave problems.
Ali Shirvani
@alishir
@agianno thanks a lot
Ali Shirvani
@alishir
Actually I want to simulate the force that a solenoid apply on a plunger.
Antonis Giannopoulos
@agianno
@alishir
gorMax will not do this
Ali Shirvani
@alishir
Thanks for your guidance
better1002
@better1002
Could not find conda environment: gprMax
You can list all discoverable environments with conda info --envs.
I have a problem with runninig gprMax
John Hartley
@jasminium
Hello. gprMax has some dependencies. These are installed into a local environment called gprMax using the conda command line tool. First you should install conda then run
Install the environment from the .yml file. The process ocumented here http://docs.gprmax.com/en/latest/include_readme.html. If you have an error please post it here.
better1002
@better1002

I have followed the instructions in the documents, and when I used the "conda activate gprMax", I got the error:

gprMax 3.1.4 is already the active version in easy-install.pth
Installed /home/tony/miniconda3/lib/python3.7/site-packages/gprMax-3.1.4-py3.7-linux-x86_64.egg
Processing dependencies for gprMax==3.1.4
Finished processing dependencies for gprMax==3.1.4
(base) tony@ubuntu:~/gprMax$ conda activate gprMax
Could not find conda environment: gprMax
You can list all discoverable environments with conda info --envs.

(base) tony@ubuntu:~/gprMax$ conda info --envs

conda environments:

#
base * /home/tony/miniconda3

(base) tony@ubuntu:~/gprMax$

John Hartley
@jasminium
try
pip uninstall gprMax
John Hartley
@jasminium
python setup.py cleanall
python setup.py build
python setup.py install
Craig Warren
@craig-warren
@better1002 @jasminium there is an issue with the current conda environment and Windows. We currently have a dependency on OpenBLAS which is not easily installable via conda for Windows. Am looking into ways around it.
Antonis Giannopoulos
@agianno
@craig-warren @jasminium Maybe we should recommend the Windows Subsystem for Linux for Win10?
better1002
@better1002
I get the gprMax from the github again, and problem solved, thanks! @jasminium @craig-warren @agianno
Craig Warren
@craig-warren
I have updated the conda environment file to remove the OpenBLAS dependency. This works on Windows and Linux. However, macOS currently requires a different conda environment file because it does need OpenBLAS as the standard MKL library causes an instability on macOS.
John Hartley
@jasminium
@agianno @craig-warren I have been using Windows Subsystem for some time now and haven't had an any issues. I have not tested the GPU code though
also it could be an idea to provide a docker application?
better1002
@better1002
I want to know how to get the geometry view of my simulation models , what's the command? thanks
Craig Warren
@craig-warren
@better1002 please read the docs, there is plenty of information and examples that show you how to do this - http://docs.gprmax.com/en/latest/output.html#geometry-output
better1002
@better1002
blob
better1002
@better1002
Problem solved,thanks
Alex-VVV
@Alex-VVV
Hi, I see that gprMax supports materials with anisotropic dielectric constants. The use case I am looking at features this kind of anisotropic material, except that its dielectric tensor is a function of space (x,y, and z). Does gprMax support this kind of use case?
Craig Warren
@craig-warren
@Alex-VVV diagonal anisotropy is supported - http://docs.gprmax.com/en/latest/features.html#anisotropic-materials
Alex-VVV
@Alex-VVV

@craig-warren I see that diagonal anisotropy is supported. I guess I wasn’t clear enough, my bad. My material as has a different dielectric constant for the x,y,z direction, so features diagonal anisotropy. My problem is this: those dielectric constants are a function of position. I.e. the value of ε_x at x=0 is not the same as at x=1.

Is this supported?

Craig Warren
@craig-warren
@Alex-VVV it is possible, but not particularly elegant. You would have to define a new material for each new position. Could be done programmatically using Python in the input file, but really depends on how much variation you have as to the number of materials you would need to create.
Siyuan CHEN
@yohanncsy_gitlab
Question for snapshot : I can create many files of images, whose format is .vti, and they will give me a 'video' in paraview. But how can I read the data in every filename.vti ?
bsesasts
@bsesasts
Hello, I would like to ask, if setting the Hertz dipole in gprmax can accurately calculate the specific field strength at a certain distance, why is the theoretical result of my calculation very different from the simulation? I will be very grateful if someone answers
Antonis Giannopoulos
@agianno
@bsesasts Our analytical comparisons with the solution of an infinitesimal dipole are pretty close (http://docs.gprmax.com/en/latest/comparisons_analytical.html) I don't understand why yours are different. Be aware that when you specify the waveform on gprMax for a Hertzian dipole you are specifying the current that runs on this dipole and not a Voltage source gap used to excite that structures of models of real antennas
bsesasts
@bsesasts
@agianno Thank you very much. After the calculation, it has basically conformed to the theory. Previously, I did not have a good understanding of the parameters and calculation of gprmax. Thank you very much.
ZPYBob
@ZPYBob
hi,I use “GPRMAX v3.1.5” software to simulate ground penetrating radar ,i have some questions .
My input file:

domain: 1.5 1.5 0.0015

dx_dy_dz: 0.0015 0.0015 0.0015

time_window: 35e-9

material: 1.0 0 1.0 0 atmosphere

material: 81.0 0.003 1.0 0 fresh_water

material: 12.0 0.004 1.0 0 L1

waveform: ricker 1 800e6 my_ricker

hertzian_dipole: z 0.15 1.3 0 my_ricker

rx: 0.25 1.3 0

src_steps: 0.02 0 0

rx_steps: 0.02 0 0

box: 0 0 0 1.5 1.5 0.0015 atmosphere

box: 0 0 0 1.5 1.3 0.0015 L1

cylinder: 0.7 0.9 0 0.7 0.9 0.0015 0.25 atmosphere

image.png
image.png
Definition of reflection coefficient:r=(√(ε_1 )-√(ε_2 ))/(√(ε_1 )+√(ε_2 ))-----------(1);r:Reflection coefficient,ε_1:Relative permittivity of the first dielectric, ε_2:Relative permittivity of the second dielectric。The phase polarity of reflection wave mainly depends on the dielectric constant of the upper and lower layers,When the relative dielectric constant of the upper medium is larger than that of the lower medium, the reflection number is positive, the phase of the reflected wave is positive, which is consistent with the phase of the initial electromagnetic wave, and vice versa.
A shown in the input file:dielectric constant of the background medium ε_1=12,atmosphere ε_2=1。According to the definition formula of reflection coefficient (1):The electromagnetic wave is projected from the surface to the top of the cavity, that is, the interface between the background medium and the air. Because of 12>1,,the reflection coefficient is r positive, so the phase of the reflected wave is positive, the phase of the reflected wave is not reversed, and it is consistent with the direct wave。For example,The initial phase of visible radar direct wave is positive (red-blue-red), the phase indicated by the blackest arrow in the A-SCAN is consistent with that of the top black arrow in the B-SCAN and the reflection coefficient formula.
At this point, one part of the electromagnetic wave is reflected at the top of the cavity, and the other part continues to propagate downward through the top of the cavity,To the bottom of the cavity, it can be considered as the interface between air and background media.Now atmosphere ε_2=1, dielectric constant of the background medium ε_1=12,Because of 12>1, According to the definition formula of reflection coefficient (1),The reflection coefficient is negative, and the phase of the reflected wave at the bottom of the cavity should be opposite to that of the direct wave, which is negative (blue-red-blue). However, the phase is visible from the green arrow in figure A-SCAN, the phase is still positive, and the green arrow in the corresponding B-SCAN indicates that the phase is consistent, positive and the phase is not reverse. This is contrary to the reflection coefficient formula. Why?
@craig-warren can you help me?please
Akshay Rathod
@AkshayRathod449_twitter
I have come across a paper regarding tree interior imaging to find whether it is hollow or not. I am trying to implement using sfcw waveform since practically it is more realizable. Can I get some support in simulation before I make hardware? sfcw waveform generation, antenna parameters, bistatic system, B scan, and data processing. I work in a research lab and we look forward to developing the hardware.
1 reply