ComPhys @comphys@qoto.org

Just made a short post about how to simulate electrostatic nonuniform charge density distributions with FEniCS; that is spatially varying charge density distributions. This could be useful for simulating things like particle beams which are commonly assumed to have Gaussian (or similar) distributions. This is a small extension of a previous post about how to simulate uniform charge density distributions.

https://wordpress.com/post/comphysblog.wordpress.com/988

#fenics #physics #opensource #python #ham

@Rovine you could use node if you've already looked at JavaScript.

@freemo works for me too now, thank you very much :)

@freemo I'm getting a gitlab 404 on video.qoto.org I'm afraid.

@mngrif nim is pretty interesting, you write something with a python-like syntax but its converted to c and compiled.

@freemo @freemo I'll sign up & upload my geometry making videos here, the instance I used originally has been down for a while now.

@Rovine well my aim isn't really to learn about blogging platforms so I wouldn't try anything too experimental, although I would consider a self hosted WordPress blog. Do you have a preferred host?

@Rovine @freemo I do this for physics and maths, if I want to learn a new subject I essentially copy a whole chapter out by hand. I often derive the results rigorously though, where books just quote an answer and I attempt some problems. I have found this to be very effective.

@freemo When I first saw this all I could think was "this is why nobody uses the divide symbol", all ambiguity disappears when it's written as a fraction.

@mycroft@mastodon.social I suppose in some areas of education its necessary, I'm coming from a physics & math background.

@mycroft@mastodon.social I wish people wouldn't use PowerPoint for teaching, I understand that its easier for teachers but I find it very unhelpful for actually learning.

@piggo Which of these features is Firefox lacking?

@Trillenial With a $50 telescope you can see other planets, all of them are clearly circular, what does he say about that? Its just a coincidence that they all happen to be showing their flat face to the earth?

I got magnetostatic simulations working yesterday, so I made a cos(theta) style dipole magnet with an iron yoke. The fields looked sensible although I didnt check the amplitudes, for the post I'll see if I can recreate the LHC dipoles!

My latest post is about using boundary conditions to assume symmetry in a finite element electrostatics problem.

To demonstrate Neumann boundaries I solve the Laplace equation for a coaxial geometry using 1/4 of the cross section. I then find the fields of a differential pair transmission line using half the cross section and a Dirichlet boundary.

This is all done with FEniCS, the open source finite element solver. #physics #python #opensource #ham #radio​ #fenics

https://comphysblog.wordpress.com/2019/07/15/assuming-symmetry-with-boundary-conditions/​​

Finally finished my post on electrostatics with linear dielectrics using the open source finite element solver FEniCS. It's surprisingly easy!

#physics, #rf, #opensource, #python, #fenics

https://comphysblog.wordpress.com/2019/01/12/electrostatics-with-linear-dielectric-materials-using-fenics/

@arteteco I have used python for ages now. I love it and I use it for everything, from data analysis to programs for controlling instruments, little scripts for automating tasks and making libraries. Is there any reason for me to learn R? It seems to have maintained its popularity despite python seeming to have taken over everything else.

@freemo @arteteco 2D data represented on a 3D plot is sure to influence those statistics.

Here's the electric potential and field overlaid for a uniform cylindrical charge distribution created using FEniCS, an opensource finite element solver. Although this is a simple analytical problem, this technique can be used for much more complicated geometries.

Next up: linear dielectrics, I've tested in both 2D and 3D and I'm ready to write it up =] surprisingly easy!

@freemo that's really cool, I'm very jealous of your electronics skills!