Archive for the ‘Tutorials’ Category

Awesome resources for mobile device development on both Android and iOS

October 7, 2012 Leave a comment

You might have shared the same frustrations with me when seeing new apps coming up on Android or iOS that are exactly what you wanted to do, but didn’t or never have time to make it real. It’s a bitter-sweet kind of mixed feeling; I’m happy that what I wanted comes true (done by others, though) and…. I am a user, but on the other hand, in my head it keeps saying “That should have been me!”.

So today I suck it up, forget the regrets, and get started. There are tons of good resources on Android and iOS app development on the Internet. Among them I found a few that are extremely good, and I just thought they might be useful for others as well, so let me share them with you.

Building mobile applications — Computer Science CS-76 (provided by Harvard)
URL: [url] You can find good quality course videos and all the materials there.
Previous years archives are also available in iTune.

CSSE490 Android Development Rose-Hulman Winter 2010-2011
URL: [iTune]

Creative Programming for Digital Media & Mobile Apps
This course is not available yet, but just by looking at the syllabus I think the content is essential, yet pretty unique.
The course is coming soon on Coursera.


How to reset root password in Ubuntu

August 7, 2012 Leave a comment

If you forgot your admin (root) password in Ubuntu. Here is a very comprehensive instruction to reset the password.

Categories: Tutorials

Recognizing music interval

July 12, 2012 Leave a comment

I found an awesome tutorial page explaining how to recognize the music interval by ear. The best thing on the page is the table discussing the feeling of each interval.


Categories: iDea, Music, Tutorials Tags:

Awesome seminars at UW

April 3, 2012 1 comment

There are some fascinating seminars sponsored by UW, and most of them are recorded:

CSE Colloquia:
Every Tuesday 3:30 pm

Yahoo! Machine Learning Seminar
Every Tuesday from 12 – 1 pm

UWTV: Research/Technology/Discovery Channel
Broadcast all the new findings, research, technology for free!!




Awesome collection of software on Ubuntu

March 27, 2012 Leave a comment
Categories: Reviews, Tutorials Tags: ,

MATLAB on Ubuntu: From Install, Make launching Icon,… to Uninstall

February 12, 2012 1 comment

Here are the steps to install MATLAB + some possible problems:

  1. Extract/mount the zipped/iso installer file. For me I extract the iso to /home/bot/Downloads/Software/ml2011bu
  2. Open the terminal (Ctrl+Alt+T), type sudo sh install
    1. You might run into the problem say:Preparing installation files …
      Installing …
      eval: 1: /tmp/mathworks_2931/sys/java/jre/glnx86/jre/bin/java: Permission denied
      bot@bot-laptop:~/Downloads/Software/ml2011bu$ cd sys

      What you need to do is to make the file “java” executable by
      from your installer folder, type

      cd sys/java/jre/glnx86/jre/bin/
      chmod +x java

      you will see that the file permission is changed from
      -rw-r–r– 1 bot bot  47308 2010-10-20 04:41 java
      drwx–x–x 4 bot bot    4096 2012-02-11 17:55 java

      Now go back to the installer folder and install it with sudo sh install, and it should work

    For more details on installation, please visit

Once the installation is finished, you may want to create a script to run the MATLAB. Here is how

  1. Go to desktop (where else is fine too)
  2. Create an empty document, let’s name it
  3. Open with gedit, and type the following
    cd /usr/share/matlabr2010a/bin/
    sudo sh matlab -desktop
  4. Open the terminal, go to desktop by typing in the terminal cd ~/Desktop
  5. make the script executable by typing in the terminal chmod +x
  6. Now you can run MATLAB by running the script by typing ./

Now, if you want to add a launching icon on the menu bar, here is how:

  1. Right click on the menu bar
  2. Edit menus>Go to Programming in the left panel
  3. Click new item and add all the information
  4. In the command, type /home/bot/Desktop/
  5. You can also change the icon by clicking at the icon on the top-left corner and choose where the icon is
    1. Here is an easy command line to download the icon
      sudo wget -O /usr/share/icons/matlab.png
    2. The icon will be downloaded to /usr/share/icons/matlab.png
  6. That’s it!

And, if you are bored with MATLAB and want to uninstall it, please follow the steps here

  1. Locate the matlab dir, mine is /usr/local/MATLAB
  2. Remove the matlab dir by
    >cd /usr/local
    >sudo rm -r MATLAB
  3. bye bye MATLAB, and you get 5GB more space hahahaha!
Categories: Tutorials Tags: ,

How to fix “sticky” wacom stylus click in Ubuntu 10.04

January 21, 2012 Leave a comment

The problem is described very well by stephanecharette “I don’t know when it started, but my Wacom stylus clicks haven’t been working right. It seems to do the “click down” correctly, but hasn’t always been doing the “click up” when I release the pressure on my stylus. This leads to a bunch of problems when Ubuntu thinks I’m holding down the mouse button, when in reality I’m not holding anything down.”  from

Although the post focuses on Ubuntu 10.10, but I think the solution is applicable to 10.04 too. It seems to me there are two solutions to solve the problem, which is posted by cnr_roxx:

  1. Compile a new driver for 10.04
  2. Upgrade to 10.10 and install 2 packages from Irie’s private repository, please see the post#5 in here

Somehow, I don’t want to upgrade to Ubuntu 10.10, so I will stick with the option 1, that is, to compile a new driver. The instruction is very well documented in

The URL links to another post, which seems to be more compact.

Just follow the steps; download, compile and install.

I also found an overview link to explain all these in just a few paragraph and it is pretty easy to follow.

For 64-bit Ubuntu 10.04, I found this the following posts are the best:

  1. The last paragraph of post#14
  2. Which links to PartIII of the post
  3. Bug report website is very helpful
  4. Setup pressure support in GIMP


[Solved] The following works!

Here is the summary on how to solve the problem from Just read the PART III “III. Configure the Wacom Bamboo P&T tablet“, and follow the instruction.

  1. type in the terminal
    gksudo gedit /usr/lib/X11/xorg.conf.d/10-wacom.conf
  2. Copy the following content to the file 10-wacom.conf and save the file
    Section "InputClass"
    	Identifier "Wacom class"
    # WALTOP needs a patched kernel driver, that isn't in mainline lk yet,
    # so for now just let it fall through and be picked up by evdev instead.
    #	MatchProduct "Wacom|WACOM|WALTOP|Hanwang"
    	MatchProduct "Wacom|WACOM|Hanwang"
    	MatchDevicePath "/dev/input/event*"
    	Driver "wacom"
    Section "InputClass"
    	Identifier "Wacom serial class"
    	MatchProduct "Serial Wacom Tablet"
    	Driver "wacom"
    #	Option "ForceDevice" "ISDV4"  # deprecated starting with
    #        xf86-input-wacom-0.10.8
    Section "InputClass"
            Identifier "Wacom serial class identifiers"
            MatchProduct "WACf|FUJ02e5|FUJ02e7|FUJ02e9"
            Driver "wacom"
    # N-Trig Duosense Electromagnetic Digitizer
    Section "InputClass"
    	Identifier "Wacom N-Trig class"
    	MatchProduct "HID 1b96:0001|N-Trig Pen"
    	MatchDevicePath "/dev/input/event*"
    	Driver "wacom"
    	Option "Button2" "3"
  3. close the file, reboot the machine, and it will work.


Categories: iDo, Tutorials Tags: