Dirk Danckaert's profile - activity

That's exactly how AntiX works. You're right that making a new version takes some time, probably more than the SDL version, but almost anyone can do it. In case you're curious: a 7.5Gb installation of AntiX on a virtual machine was squashed in a 2.0Gb iso file, that I could transfer to a live USB. That leaves ample space for persistence and a second, windows readable partition. It worked on first try, apart from some tweaking of keyboard settings that I need to look into. Thanks again and I'll sure try SDL.

Thank you so much. Worked like a charm. In case someone else is looking for this information: I had to install the build-essential package in order for gcc to be able to locate stdio.h, and the zeromq package had to be installed BEFORE the pyzmq package, which makes sense of course. Also, I had Tornado installed already before. That did the trick, no problems whatsoever.

I tried to find the information you gave me on sagemath.org, but got lost on the page http://www.sagemath.org/download-pack... . When I look at it now I see the sought-after link immediately of course. Also, I was confused by the links in the section Additional Packages on that page. These links bring you straight back to the same page. Shouldn't this section be removed?

When I have finished this job, I'll surely take a look at the Sage Debian Live system, and maybe provide some feedback. I would love to contribute something, but I'm afraid I'm not nearly knowledgeable enough to be useful. I just make use of AntiX, a less well known Debian Linux System, that takes care of all the subtleties involved in converting a running Linux system, with essentially any applications you care for, into a live USB key. My first try, last year, had Sage 6.2 without iPython, and a full Linux installation, with applications, also on approx. 3Gb.

I would like to use the ipython notebook on an older version of sage. Since I want to make my own live USB with Sage and some other programs it makes a big difference using the 3Gb 6.2-version or the 4.5 Gb 6.7-version. I tried to follow the instructions in http://pub.ist.ac.at/~jguzman/doc/pro..., but these are not working anymore. The command

sage -i zeromq

returns an invalid syntax message. Is what I'm trying to do still possible? Or do I HAVE to use the more recent sage incarnations?

I just did a fresh install of SAGE 5.3 on a clean Ubuntu 12.04 LTS, with essentially no problems at all. Now I would like to use it as a cell server too. Can anyone point me to a page with up-to-date instructions on how to do this?

Just to be clear: I want to use the same SAGE installation as both a notebook server AND a cell server.

Yes of course, repeated functiondefinitions certainly seem suspect. I'll test that. I used to avoid this, but now I make a test page (with only one cell, and all code included) and then paste it in its entirety into the bigger web page. Inserting html-code in this kind of dynamic php-generated pages is tricky, and I thought this way I would minimize the chance for making errors, that sometimes screw up the whole page and are hard to correct. The header of the page, unfortunately, is inaccessible, but defining the cell function in the body seemed to work too. Thanks.

As far as I know, no. You can shorten the password though, but I never tried an empty password. And maybe your browser can take care of automatically providing credentials? Firefox proposes all the time to keep track of my passwords.

Has anyone experienced the following: when embedding multiple sage cells in a single web page, only one of them is actually displayed by firefox. Opening the same web page in Chrome shows all cells as active. Here's an example:

http://moodle.snorduffel.be/course/vi...

(The page also contains some java-stuff, so you can also expect some error messages related to java applets not being trusted). The page contains 4 different Sage cells, but the only one I see is the one with hidden editor box. Each cell on its own displays just fine in firefox, but the four of them together don't.

Is there anything I can do on the sage side? Or is this purely a firefox problem?

Could you be a little more specific? You mention VM, so am I right that you run Sage in a virtual machine under Windows? As I understand it, automatic login works on the server machine only (that is, when you are logged in on the CentOS machine itself) and never when you contact the server from another machine in a browser window.

Well, as a matter of fact, I think it should output a closed form. I'm approaching the question from a didactical point of view. It may well be that treating these questions as linear recurrences is a more fundamental point of view, but students and even many teachers are not aware of that. I checked Wolfram Alpha, and that gives the closed form answer straight away. I just want to know how I can prod SAGE to do something along the same lines.

Thank you for the 'find' syntax. It was precisely in such an exclude file that the error was made.

It's not that hard to find a closed expression for the remainder of the polynomial $x^n$ modulo $x^2-5x-2$. But I don't seem to manage it in SAGE.

n=var('n')
R=PolynomialRing(RationalField(),'x');R
x=R.gen();x
mp=x^2-5*x-2
S=R.quotient(mp,'a')
a=S.gen();a^2
a^5

works as expected, but replacing the last line with a^n gives an error (non-integral exponents not supported). I understand a general variable is not a SAGE integer, but how DO I make clear n is supposed to be an integer?

In the same way, it's not that hard to calculate the symbolic n-the power of a small, say 2x2, matrix, but the straightforward aproach of simplifying A^n gives the same error (non-integral exponents not supported).

I checked wolfram alpha for the symbolic power of a matrix, and immediately got the expected answer for [[1,2],[3,4]]^n .

Once more I answer my own question. I'll try not to do so anymore in the future.

The problem has nothing whatsoever to do with SAGE itself. It's caused by a sloppy configuration file used for rsync. As a result there is a confusion between the root folder /media/ and a subfolder media/ deep within SAGE. It took some time for me to locate the folder .../media/... within SAGE, but then I saw that this folder was indeed copied, but left empty by rsync. From there on I quickly found the reason why.

I'm sure there's a simple command that could have told me where to find media/ in a second, but I'm far from a linux wizzard, and the SAGE folder has a quite overwhelming tree structure.

Feels a bit silly to answer my own question. I just didn't have enough patience. After waiting for maybe 5 minutes, I eventually received a time-out, and the rest of the page was displayed. I was then able to edit the page and remove the unnecessary references to aleph.sagemath.org

In my school we run a Moodle site. The opening page in my math course downloads two scripts from aleph.sagemath.org. The scripts were useful in the past when I displayed a few sage-cells, which have been removed later. The references to these scripts however were only visible in the page source and were not removed.

Now it seems the server at aleph.sagemath.org is unreachable, and the page hangs when trying to contact it. I'm unable to view it, and unable to edit it. Is this a temporary problem or has this server disappeared for good? Any suggestions on how to repair the situation?

I just downloaded 2014-05-25-sage-6.2-debian-wheezy-live-3.0.5-1.img, the install file for the Sage Live Cd that I wanted to experiment with. I was expecting an .iso file that I could transfer to a USB pendrive, but I don't know what to do with this .img-file. I can't seem to find the appropriate instructions on the Live CD webpages.

Can someone provide me a useful link to the installation instructions?

I guess I just ran up against one of those maxima things again, but I thought I would signal the problem anyway.

I would have expected Sage to simplify

sinh(log(1+sqrt(2)))

(it is 1), but Sage doesn't. It doesn't return True to the following either

arcsinh(1)==1+sqrt(2)

or am I missing something?