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As a summary: I wanted to install the latest SCilab, which is not available in the Software centre. I downloaded the tar.gz file from the website. I then followed the instructions from response 7 here How to install a .tar.gz (or .tar.bz2) file?. This didn't work for me. So I removed the file (I think), and extracted the file a different way and ran the program from there.

Okay, so I downloaded Scilab from their website as a tar.gz file.

I then copied the file to /opt:

 sudo cp [download name].tar.gz /opt/ 

I then extraced the file and deleted the tar.gz file:

 sudo tar -xvf [download name].tar.gz
sudo rm -rf [download name].tar.gz 

I found the folder. It was called Scilab-5.4.1. I think the next step changes the "access" settings, and so I changed it as follows:

 sudo chmod 770 Scilab-5.4.1/ 

So this is owner and group permission to read, write and execute.

I then tried the symbolic link thing:

 sudo ln -s /opt/Scilab-5.4.1/ /usr/bin/scilab 

After this, I tried different ways to run the programme from the terminal, but to no avail. I then looked for the Scilab folder, which I found in opt. I tried to delete the folder "Windows-style" (send to recycling bin) but it wouldn't let me. I also tried purge from the terminal but it couldn't find the programme. I then used:

 sudo rm -r /opt/Scilab-5.4.1 

The folder disappeared. After this, I downloaded the file again, and transferred it to opt in the process:

 sudo tar xzvf [download name].tar.gz -C /opt/ 

I then went to the folder (in terminal):

 cd /opt/scilab-5.4.1 

And opened Scilab:


This seems to work. However, there is a Scilab programme logo in the launcher (Unity), but it disappears on closing the programme and there is no logo in the recently used programmes section in the dash.

I want to know that was there an error in my installing process done in the previous unsuccessful install, since I can't find the Scilab logo anywhere ?

Why first method didn't work but the second, simpler method, seemed to work okay (I can at least open the programme) ?

(The final peculiar thing is my "history" in the terminal: using the up-arrow to navigate to previous commands, the history suggests I didn't use rm -r, even though I am almost certain I did.)

share|improve this question
If the steps of the first installation try are literal, you forgot to cd /opt before decompressing the file --- so Scilab ended in your current directory. The symlink ins wrong, too. Braiam answer should take care of the rest. – Rmano Nov 22 '13 at 21:22
Thanks, Rmano. I omitted some of the "less important" steps such as changing the directory to keep it more succinct. I am not sure I removed the programme correctly. Let us say I wanted to run Scilab. I have two Scilab locations: one in /opt/Scilab-5.4.1 and one in /home/jayjay/scilab so I can use cd to go to both locations and run ./bin/scilab. Is this duplication a normal event in Ubuntu? (I'm new to the whole Linux thing) Many thanks – Jayjay Nov 23 '13 at 0:00
No, this is not normal. It is possible that Scilab creates a directory in your home to save data and settings, but it's not normal to have two copies of it. – Rmano Nov 23 '13 at 0:06
Thanks, Rmano. I tried to remove as much of Scilab-5.4.1 as I could using get-apt remove or purge and using rm -r. There are still files and hidden folders scattered around in directories I have never heard of. But I tried to remove as much as possible. I then downloaded the tar file again and extracted to /opt/ I am assuming any files not deleted that are necessary are simply replaced with the new extraction, and those that are present from previous wayward Scilab downloads will be ignored: they won't affect the most recent extraction, will they? – Jayjay Nov 23 '13 at 16:28
Probably you're ok. – Rmano Nov 23 '13 at 17:25
up vote 2 down vote accepted

To make Scilab present in the path, you must modify your symbolic link creation to:

sudo ln -s /opt/Scilab-5.4.1/bin/scilab /usr/bin/scilab

That way you can type scilab in the shell and open it. For creating the icon:

gedit ~/.local/share/applications/scilab.desktop

Now add the following content:

[Desktop Entry]

Now you can pin it to the dash or just searching for "Scilab".

share|improve this answer
@Rmano. Thanks to both of you for the help. I followed your advice: I created a symbolic link, which was successful. For creating the icon, the path you gave didn't work, I found where the *.desktop files all seem to be kept; I then copied the scilab.desktop file from the /opt/ folder to this other folder and changed StartupNotify and Exec to match your information. It seems to work; however, how do I change the icon from a question mark to the Scilab logo? Many thanks. – Jayjay Nov 23 '13 at 16:19
You must add/edit the Icon= stanza in the desktop file and point fill it with the full path, example: Icon=/usr/where/all/icons/are/scilab.ico or something. – Braiam Nov 23 '13 at 16:31
Thanks Braiam. I was just doing some research and found the logo in the icons section of /opt/Scilab and used gedit to change the icon path for the scilab.desktop file in /usr/... I used the 48x48. This is similar to what you recommend except I can;t find a "logo repository" where all logos are kept. Instead, I used the seemingly very specific 48x48 logo (since this matches the launcher icon size). – Jayjay Nov 23 '13 at 16:44
@Jayjay is not a logo repository, but I guessed the Scilab would have more icons (16x16, 48x48, 128x128, etc) so I was just giving you a example of the path. BTW, if my answer solved your question or there is some inacurancies feel free to edit/accept it. – Braiam Nov 23 '13 at 17:03
Thanks Braiam. I thought you meant a repository in a similar fashion to the *.desktop repository I found in /usr/... If the 48x48 logo works fine - which it seems to - I'll leave it at that. Many thanks for the help. – Jayjay Nov 23 '13 at 17:09

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