RPi Education/Manual

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< RPi Education
Revision as of 07:21, 25 April 2012 by Yoda (talk | contribs) (Perl)
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Please add any contributions to the educational user manual here. These should take the form of step-by-step guides or listings with descriptions. Alternatively, email your contribution by taking a look at this Raspberry Pi forum posting.



The objective is to educate people in computer science.


Cheap hardware with 1/2 open specifications allow the masses to learn modern computer science.

  1. Plug in your RPi to your monitor with the hdmi and usb cable
  2. Plug in your mouse and keyboard to your monitor
  3. Plug in your monitor power and turn it on.


Linux is used, it is open source, user friendly, and technically capable.

Language Selection

Beginners should select a high level language. Advanced users may select different languages combinations depending on the available libraries, programming paradigm, and optimizations.

All code is executed in binary assembled from assembly code compiled from a language sometimes in-turn compiled from other higher level languages.

There are 2 main interfaces for most all applications in linux CLI, and GUI, while GUIs are user friendly CLIs are more simple to build and can be used as building blocks for more complicated tools/toys.

It is considered good programming to use an iterative approach, using existing tools and patterns as much as possible, as such it is customary to start with a hello world:


Bash is the language of the terminal.

  1. open the termonal application
  2. type: echo Hello World!

echo Hello World!

That was a computer program,

If you want to learn more about the echo command you can type man echo (press q to quit)

man echo

Now let's make our program into runnable file:

  1. nano hi.sh
  2. echo Hello $1!
  3. [Ctrl]+[x],[y],[enter]
  4. bash hi.sh Tux

bash hi.sh Tux

Which should ouput:

Hello Tux!

(vim, and gedit are other editors you may with to use.)


Make a file called hi.py, put print("Hello, world!") in it and run it with python hi.py

Now a GUI version:

...//TODO format code in wiki...


Features, libraries, and limitations.


Create a text file called 'hello.py', with the following contents

print "Hello World!"

To run the program, type the following

python hello.py

It should respond with:

Hello World!


C and C++ are often put together, but are indeed two similar but different languages.


Create a Text File called 'hello.c' which contains the following:

#include "stdio.h"
void main() {
        printf("Hello World!\n");

Now compile the file using 'cc' , like this:

$ cc hello.c

If all went well, there will no error messages and a new file called 'a.out' should have been created by the compiler.

$ ls
hello.c a.out

To run your program type:

$ ./a.out

It should report back with your message:

Hello World!


For starters the famous "Hello world!" example. Save the following code in a file called helloworld.cpp in a directory of your choice (e.g. ~/cpp). The filename can be chosen arbitrarily, but should describe the content.

 //Compile with: g++ helloworld.cpp -o helloworld
 #include <iostream>
 using namespace std;
 int main () {
     cout << "Hello world!" << endl;
     return 0;

Open a terminal and switch to the directory, which contains the saved file.

cd ~/cpp

Make sure with ls that you are in the correct directory. It should output helloworld.cpp and all other files in this directory (if any).

Now it is time to translate your code so your computer can understand it. This is called compiling.

g++ helloworld.cpp -o helloworld

If everything went ok, nothing is printed. Now run your program.


This outputs Hello world! on the command line.



Useful tools and fun toys.




A "Hello World" example in Perl.

Create a file called 'hello.pl' in a directory of your choice, with the following contents:


print "Hello World!\n";

To run your program type:

perl hello.pl

It should respond with:

Hello World!


Create a text file called 'Hello.java' with the following content:

public class Hello {
    public static void main(String[] args) {
        System.out.println("Hello World!");

Now compile your file as follows:

$ javac Hello.java

Notice how a new file was created after compilation:

$ ls
Hello.class Hello.java

To run your program:

$ java Hello

It should respond with

$ Hello World!





Algorithms, Heuristics, Design Patterns, and Optimization.




Software tools and disciplines

  • Version Control
  • Software Building
  • Change tracking
  • Test Driven Development
  • Writing software for someone else (User Stories and Use Cases)