Raspberry Pi Forums

szhorvat

There is a new version of IGraph/M out, with Raspberry Pi support. For quick and easy installation, go here: https://github.com/szhorvat/IGraphM#installation If you use this package on the RPi, please respond and let me know. I am trying to decide whether it is worth supporting this platform. https:...

szhorvat

There is a new version of IGraph/M out. Testing, especially on the Raspberry Pi, is appreciated.

https://github.com/szhorvat/IGraphM#installation

szhorvat

Now that Mathematica is back in the Raspbian repos, I re-added Raspberry Pi support to IGraph/M.

If you use Mathematica on the RPi, check it out. It provides more than 250 new graph-related functions. Please join the Gitter chatroom for any feedback you might have.

szhorvat

It's great that Mathematica is back in the Raspbian repos. Seeing that we can count on Mathematica being available for the Raspberry Pi, I re-added RPi support for my network-analysis and graph theory package, IGraph/M.

szhorvat

Take a look at

https://mathematica.stackexchange.com/

and

http://community.wolfram.com/

to see what people use it for. Mathematica is an essential tool for many scientists.

szhorvat

The IGraph/M 0.3.91 prerelease is now available for Raspbian Jessie: https://github.com/szhorvat/IGraphM/releases

Any suggestions or bug reports are most welcome.

szhorvat

FourierTransform is not what you need. That function computes a symbolic transform. You need Fourier instead to use on numerical data.

To generate an array, look up Table. To plot it, or its Fourier transform, use ListPlot. Fourier returns complex quantities, so you'll probably want Abs.

szhorvat

It does work, but PlotPoints doesn't exactly do what you think. It sets the initial number of points. Mathematica may automatically add additional points adaptively for a better quality plot. MaxRecursion controls the number of refinement steps when adding points. To see all the plot points, use the...

szhorvat

IGraph/M version 0.2.0, the igraph interface for Mathematica is released today. It can be downloaded from https://github.com/szhorvat/IGraphM/releases This version comes with Raspberry Pi support. IGraph/M complements Mathematica's graph theory and network analysis functionality with many new functi...

szhorvat

This does appear to work now in the latest, 2015 Jan 29 version.

szhorvat

I would recommend exporting the frames one by one as PNG images, then encoding the video afterwards. Yes, Mathematica can export videos directly, but creating frames separately gives you more control and makes it easy to interrupt or resume the process. I do this even on fast desktops, and I wouldn'...

szhorvat

All built-in symbols in Mathematica have names starting with a capital letter, no exception. Infinity, Pi, I, E, all of them are capitalized. This makes it easy to avoid conflicts with builtins when you create your own symbols: just use lowercase names for your own ones. Also, all of these names are...

szhorvat

Certain operations, such as exporting graphics, require the Mathematica "Front End". The Front End is the program that shows Mathematica's GUI. If you run Mathematica in command line mode, and try to export graphics, it will automatically start up the Front End for you without any visible windows, s...

szhorvat

Thanks for the responses. This new version came out just a few days after I posted my question.

szhorvat

What is the latest Mathematica version for the Raspberry Pi as of 2015 January? I seem to have the 2014 August 4 version, which has $VersionNumber == 10 and $ReleaseNumber == 0.

Is the equivalent of Mathematica 10.0.2 ($ReleaseNumber == 2) available?

szhorvat

Thank you all for the replies. Is the information I can find about "backpowering" also apply to the situation I described (i.e. using the Y cable with a separate power supply)? Or does it only apply to powered USB hubs?

szhorvat

FTrevorGowen wrote: ** I have yet to find such a hub that costs less than the Pi itself so I prefer to use USB HDD's that can be externally powered w/o the use of a "Y cable".

Thanks for the response. Are you aware of any problems with the 7 port hub mentioned here?

szhorvat

I have an external hard drive that I would like to connect to the Raspberry Pi. This hard drive has a single USB connector and must be powered through it. It came with a cable that has two USB A type ends to be connected to two USB ports of the same computer, for sufficient power. The Raspbery Pi ca...

szhorvat

I've never had the time to write a C library/API. MMAL is the best best for generic code, but it's a bit of a handful, and undocumented - raspistill/vid are in effect the documentation. Avoid OpenMAX. It's a right PITA to use. Not sure how well the community based API's have been doing. So based on...

szhorvat

There's an (official?) Python API for accessing the camera, and there's raspistill/raspivid/raspiyuv for command line access. What is the best/recommended way to access the camera from C (or C++)? My priority is ease of learning, which means that I prefer well documented complex stuff to udocumented...

szhorvat

The code is closed source I am afraid. And horribly complicated (tuning files are about 70k lines long). Low framerate is interesting. How low? Do you get the same at normal framerates? I'll ask around to see if that might cause oscillations. Have you tried different exposure modes or fixed gains? ...

szhorvat

Lots of back lighting is always going to be a pain. And as mentioned above, the tuning hasn't had a huge amount of time spent on it (you can spend man years!). Enough to get a decent image, plus a little bit more, but dealing with this sort of edge case stuff is very time consuming, and there isn't...

szhorvat

Has anyone else encountered similar problems, i.e. oscillations in the exposure that do not die off? It looks like the auto-exposure control is not well tuned ...

szhorvat

The Pi camera supports spot metering (raspistill -mm spot). Where is the metering spot and how large is it? How can I move the location of the metering spot? (I'm willing to use any camera API that supports this if not possible with raspistill/raspivid.) Use case: I'm taking a time lapse during vary...

szhorvat

Take a look here. There's a section with tutorials.

Search found 28 matches

Re: Announcement: igraph interface for Mathematica

Re: Announcement: igraph interface for Mathematica

Re: Announcement: igraph interface for Mathematica

Re: Matematica removed from raspbian image

Re: i dont see any point

Re: Announcement: igraph interface for Mathematica

Re: new to Mathematica but have used matlab.

Re: PlotPoints does NOT work

Announcement: igraph interface for Mathematica

Re: How to Run Tests in Command Line Wolfram

Re: How to create animation?

Re: Mathematic query

Re: Save plots in Mathematica-Command line

Re: What is the latest Mma version as of 2015 January?

What is the latest Mma version as of 2015 January?

Re: Power external HDD: safe to connect both to RPi and char

Re: Power external HDD: safe to connect both to RPi and char

Power external HDD: safe to connect both to RPi and charger?

Re: Best way to access camera from C

Best way to access camera from C

Re: Exposure control goes into oscillation during video reco

Re: Exposure control goes into oscillation during video reco

Re: Exposure control goes into oscillation during video reco

Spot metering: how to move the spot?

Re: Any Tutorial for Wolfram?