Emacs tip: Global indentation

Global Indentation

In order to get what people like to call smart indentation on Emacs, the easiest way is to add a couple of lines to the .emacs configuration to declare that every newline should be indented.

(define-key global-map (kbd "RET") 'newline-and-indent)
(setq-default indent-tabs-mode t)

The first line defines a global¹ shortcut ² for the command newline-and-indent assigned to the RET key (known Enter).

The second line turns-on (the t at the end means true) the TAB indentation… if it’s not turned-on by default!

Footnotes:

¹global means that it is valid for any emacs mode

²In emacs-lisp it is called define-key

Author: Oscar Castillo-Felisola

Created: 2013-11-07 Thu 15:08

Emacs 23.4.1 (Org mode 8.2.1)

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Linux TIP: Installing Skype 4.2 on Debian

According to this post, the instructions to install the latest Skype on Debian are

$ sudo dpkg --add-architecture i386
$ sudo apt-get update
$ sudo apt-get upgrade
$ sudo dpkg -i skype-debian_4.1.0.20-1_i386.deb
$ sudo apt-get install -f
$ sudo dpkg -i skype-debian_4.1.0.20-1_i386.deb

I followed these instructions and it worked alright on my second try!… Don’t know why the first time my Skype account was not recognised.

Ok, if it work… just remember that credit is not mine!

Cheers

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Author: Oscar Castillo-Felisola

Created: 2013-10-14 Mon 11:25

Emacs 23.4.1 (Org mode 8.2.1)

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Installation of SageManifold

Hello again! If you are looking for a Differential Geometry tool, a Sage package which is under development is SageManifold. Let’s see how to install it.

1. Download the package using the link (currently v.0.2). I’d assume it is saved on your Downloads folder.
2. Assuming you have SAGE installed, and you have created an alias to call it (see my previous post), run the following command

   $ sage -f ~/Downloads/manifolds-0.2.spkg

3. To generate the documentation (in case you don’t want to or cannot download it), use either of the commands

   $ sage -docbuild sagemanifolds pdf
   $ sage -docbuild sagemanifolds html

4. In order for using the package, start your WorkSheet with the command line

   from manifolds.all import *

Have a nice calculation!

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Installing SAGE from the source on Debian.

I’m installing SAGE¹ v.5.12 on my laptop which runs Debian. Here I describe the procedure.

1. Since there is no Debian binary package, you should download the source code. Here the link.
2. When it finishes, open a terminal C-M-t (sorry for the emacs notation, it means Ctrl+Alt+t)
   • Go to the Downloads folder (or the right place where the tar file was saved)

   $ cd ~/Downloads

   • Untar the file

   $ tar xvf sage-5.12.tar

   • Move to the sage-5.12 folder just created

   cd sage-5.12/

3. Install the dependencies of the first line. Optionally install LaTeX and ImageMagick using the second line. (NOTE: superuser power is needed to run the below code)

   $ sudo apt-get install -y gcc perl m4 dpkg-dev 
   $ sudo apt-get install -y texlive imagemagick

4. In machines with more than one core, the instruction to perform parallel compilation is (yo should change the “4” by the amount of cores in your machine)

   $ export MAKE="make -j4"

5. Now is time to compile the code.For a local compilation, run

   make

   For a
   You can relax, go and have a coffee, because the compilation may longs one hour (or more depending of the machine specifications).

6. For running the software after the installation is complete, run (on the SAGE directory) the command

   $ ./sage

   • I don’t like to move to the SAGE directory every time and then run the ./sage command, therefore, I tend to create an alias on my ~/.bash_aliases file,

     $ echo "alias sage="sh ~/Downloads/sage-5.12/sage" >> ~/.bash_aliases

     This command adds the line alias sage="sh ~/Downloads/sage-5.12/sage at the end of the file ~/.bash_aliases, you can do it by hand with your favourite editor (gedit, emacs, nano, vim, …)

   • If you refresh your terminal (or open a new one) you just have to run the command sage to start SAGE. Additionally, the notebook environment can be started directly from the terminal by using the flag -n,

     $ sage -n

Hope you find this post useful! Remember to leave your comments or suggestions.

Enjoy!

Footnotes:

¹SAGE is an open source mathematical software which allows numerical and symbolic manipulations

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Install Mathematica 9 on Linux

• Create a folder called Mathematica on the /opt/ directory

  $ sudo mkdir -p /opt/Mathematica

• Move the installed file to the created folder

  $ sudo mv MathemacicaInstaller.sh /opt/Mathematica

• Run the Installer

  $ sudo sh MathemacicaInstaller.sh

• After the installation you just have to register your Mathematica software.

Author: Oscar Castillo-Felisola

Created: 2013-09-16 Mon 13:32

Emacs 23.4.1 (Org mode 8.0.7)

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