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vjoel

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Mathematician, rubyist, former transportation researcher, interested in distributed computation, simulation of networks of hybrid automata.

https://github.com/vjoel

@JoelVanderWerf

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Enjoyed playing with blocksim. Have you considered aiming for a different market than matlab/simulink? One thing that simulink cannot do well is dynamic, reconfigurable networks of components (for example, UAVs or autonomous vehicles, but also game sprites). For this purpose, some smart people (not me) at UC Berkeley developed a language called SHIFT and applied it to platoons of automated cars and trucks back in the mid 1990s. I rewrote it as a ruby DSL that generates C code: https://github.com/vjoel/redshift. It would be fun to have something like that in a browser, with animations.

Love zim wiki, use it every day, but: it still doesn't detect file change on disk. So after (1) edit on host A, (2) sync with git (or rsync or btsync...), (3) go to already open edit window on host B, you can end up editing a stale buffer, and then you have to merge manually.

Still better than the alternatives.

Took me a long time to notice that my cursor movements were injecting disturbances into the fluid. What physical laws govern these points, and how is the cursor perturbing them?

There are quite a few quad-core, single-board, fanless ARM computers: utilite, wandboard, odroid, udoo, radxa.

I have two odroid U2 that I use for testing distributed and multithreaded code. One odroid core (exynos 4412 @1.7GHz ) is more than 8x as fast as the pi, for some numerical simulation code (ODEs). Storage is eMMC, so should be faster than the class 10 SD card in a Pi. It was very easy to get Linaro set up on them (for headless use, as compute servers). Recommend highly.

I use my two RPi for file serving, backups via rsync and btsync, limited web (one is at a remote location).

There's a utilite pro on order as well, but they are a bit backlogged, as I understand it. I'm looking forward to the 2x Gb eth (odroid is 100Mb) and faster bus and disk speeds.

I used to do a lot of scientific programming in ruby. I got around the slowness of the interpreter by generating C code on the fly. You don't have to give up Ruby as the DSL and utility language. It's the best of both worlds, if you can invest the time to set up the code generating machinery.

As I posted on the coderwall discussion: If you are working with continuous systems (ODEs) or hybrid systems (ODEs plus discrete state transitions and dynamic dataflow networks), then you might be interested in RedShift. For example, here's a simulation of a simple thermostat controller: https://github.com/vjoel/redshift/blob/master/examples/therm.... (I am the author of RedShift. You can find my RubyConf 2009 presentation on the confreaks site.)

In XFCE, you can move windows by pressing them against the side of the screen. Go to Settings, WindowManager, Advanced. Click "Wrap workspaces when dragging..." and choose your desired edge resistance.

However, I prefer to re-map CapsLock to <Hyper>, and define <SHIFT>-<HYPER>-Up to move window to workspace up, and so on.

Can't help with the stealing, sorry.