## Integrating Sage with LyX

I have been interested in the LaTeX typesetting system, but not in actually learning the extra syntax. And so I’ve been using a WYSIWYM GUI named ‘LyX‘. The .TEX-Files LyX exports are suitable to creating HTML Files, which in turn can contain typeset Math, by way of scripts, that provide MathJax code.

But then one compromise this has meant for me was, that I could either typeset Math which I had written myself, or that I could do Computer Algebra, the latter through the use of ‘wxMaxima’, which has its own system of exporting to HTML. But so far, I could not do both in one document.

Well, now that I have ‘SageMath’ and ‘SageTeX’ installed, I can do both within the same document. It’s possible to integrate SageTeX into LyX. The following is an article which explains how to do that, under the assumption that the user has both SageTeX and LyX installed:

https://wiki.lyx.org/Layouts/Modules#toc7

There is an important way in which I needed to modify the instructions however, to get the two working. First of all, there is a list of files to download – LyX does not support SageTeX out of the box – that the article above links to. Out of those files, ‘setup.sh’ is absolutely useless on a modern Linux computer. The following files from the repository above are essential:

1. sage.module
2. preferences
3. compile-pdf-sage.sh
4. example.lyx

The file ‘preferences’ needs to be edited, in that its last line needs to be uncommented.

The file ‘compile-pdf-sage.sh’ needs to be edited, in that the first two lines need to be commented out, and the next three lines which are commented by default, need to be uncommented. Then:


(As user:)

$cp sage.module ~/.lyx/layouts$ cat preferences >> ~/.lyx/preferences

(As root:)

# cp compile-pdf-sage.sh /usr/local/bin
# chmod a+x /usr/local/bin/compile-pdf-sage.sh




Then, within the GUI of LyX, one gives the command ‘Tools -> Reconfigure’. One shuts down and restarts LyX. Next, one opens ‘example.lyx’ to test the setup. The following is the document which I finally obtained (successfully), which was provided by the Web-site above (not written by me):

http://dirkmittler.homeip.net/sg_lyx_1.pdf

Enjoy,

Dirk

## I just installed Sage (Math) under Debian / Stretch.

One of the mundane limitations which I’ve faced in past years, when installing Computer Algebra Systems etc., under Linux, that were supposed to be open-source, was that the only game in town – almost – was either ‘Maxima’ or ‘wxMaxima’, the latter of which is a fancy GUI, as well as a document exporter, for the former.

Well one fact which the rest of the computing world has known about for some time, but which I am newly finding for myself, is that software exists called ‘SageMath‘. Under Debian / Stretch, this is ‘straightforward’ to install, just by installing the meta-package from the standard repositories, named ‘sagemath’. If the reader also wants to install this, then I recommend also installing ‘sagemath-doc-en’ as well as ‘sagetex’ and ‘sagetex-doc’. Doing this will literally pull in hundreds of actual packages, so it should only be done on a strong machine, with a fast Internet connection! But once this has been done, the result will be enjoyable:

I have just clicked around a little bit, in the SageMath Notebook viewer, which is browser-based, and which I’m sure only provides a skeletal front-end to the actual software. But there is a feature which I already like: When the user wishes to Print his or her Worksheet, doing so from the browser just opens a secondary browser-window, from which we may ‘Save Page As…’ , and when we do, we discover that the HTML which gets saved, has its own, internal ‘MathJax‘ server. What this seems to suggest at first glance, is that the equations will display typeset correctly, without depending on an external CDN. Yay!

I look forward to getting more use out of this in the near future.

(Update 09/15/2018, 21h30 : )

## Firefox Quantum now available under Debian Linux

There has been an ongoing subject, concerning Debian distributions of Linux, and Firefox upgrades. The Debian users, at least if they were restricting themselves to standard repositories, were being held back to a version of Firefox, which was referred to as Firefox-ESR, which stands for ‘Extended Support Release’. This release was receiving regular security patches, but no major upgrade in the version number, which meant that it was always at some sub-version of Firefox 52…

Well only yesterday, my two Debian / Stretch computers, which I name ‘Plato’ and ‘Klexel’, finally received a much-anticipated upgrade to Firefox Quantum, which is also known as Firefox-ESR, v60…

I am happy with Firefox Quantum, but perhaps only, because certain earlier, unstable versions of it, never made it into the Debian repositories? There is one observation about this updated browser-version which I need to make. As was announced, Mozilla dropped support for the old, ‘Netscape Plugin API’, which I had still been using to custom-compile plug-ins. Instead of using this API, up-to-date developers are being asked to use the ‘firefox-esr-dev’ package. but alas, the last time I checked, this package was not up to version 60… This package was still at version 52…

## I no longer have Compiz-Fusion running on the LXDE-based computer, named ‘Klexel’.

According to this earlier posting, I had run in to stability issues with my newly-reinstalled Linux computer, which I name ‘Klexel’. Well, the only sensible way, finally, to solve those problems, was to deactivate ‘Compiz Fusion’, which is a special window-manager / compositor, that creates a desktop cube animation, as well as certain other effects, chosen by the user out of a long menu of effects, but which needs to run on the graphics hardware, using OpenGL.

Even though Compiz Fusion is fancy and seems like a nice idea, I’ve run in to the following problems with it, in my own experience:

• Compiz is incompatible with Plasma 5, which is still my preferred desktop manager,
• If we have a weak graphics-chip, such as the one provided on the computer named ‘Klexel’ using ‘i915 Support’, trying to run Compiz on it forces the so-called GPU to jump through too many hoops, to display what it’s being asked to display.

Before a certain point in time, even a hardware-accelerated graphics chip, only consisted of X vertex pipelines and Y fragment pipelines, and had other strict limitations on what it could do. It was after a point in time, that the “Unified Shader Model” was introduced, whereby any GPU core could act, as a vertex shader core, as a fragment shader core, etc.. And after that point in time, the GPU also became capable of rendering its output to texture images, several stages deep… Well, programmers today tend to program for the eventuality, that the host machine has ‘a real GPU’, with Unified Shader Model and unlimited cores, as well as unlimited texture space.

The “HP Compaq DC7100 SFF”, that has become my computer ‘Klexel’, is an ancient computer whose graphics chip stems from ‘the old days’. That seems to have been an Intel 910, which has as hardware-capability, direct-rendering with OpenGL 1.4 , the Open-Source equivalent of DirectX 7 or 8 . Even though some Compiz effects only require OpenGL 1.4 , by default, I need to run the computer named ‘Klexel’ without compositing:

Also, before, when this was the computer ‘Walnut’, it actually still had KDE 3 on it! KDE 3 was essentially also, without compositing.

It should finally be stable again, now.

By comparison, the computer which acts as Web-server and hosts this blog, which I name ‘Phoenix’, has as graphics chip an Nvidia “GeForce 6150SE”, that is more powerful than the Intel ‘i915′ series was, is capable of OpenGL 2.1 , equivalent to DirectX 9 , but still predated the Unified Shader Model chips. Microsoft has even dropped support for this graphics chip, because according to Microsoft, it’s also not powerful enough anymore. And so up-to-date Windows versions won’t run on either of these two computers.

(Update 09/04/2018, 18h20 : )