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Archive for October, 2012

Frankfurter Buchmesse – report and tipps

Posted by Ed on October 15, 2012

This weekend I went to the Frankfurter Buchmesse (Frankfurt book fair). Here is a little report: The book fair started on October 10 and lasted till October 14. Only on Saturday and Sunday it was open for the broad audience. First let me tell you that the halls are really huuuuge. It is almost impossible to view everything on a single day which is why I visited the book fair on Saturday and Sunday.

Also, I apologize in advance for writing so many things in detail that seem to be pointless but they will be a reminder for next year.

Saturday, October 13:

– From Frankfurt Main Hauptbahnhof I took the U4 to Frankfurt Messe.

– I arrived at the Frankfurt Messe where the book fair takes place at 13:30. There are two entrances. Just follow the mob that is probably also on its way to the book fair.

– When you reach the building inside you have to take the escalator to the first floor. Only there you can buy a ticket. A day ticket costs 16€, but you get a discount if you are a student or retiree. I only paid 10€ because I’m enrolled as a university student. Otherwise you can also buy a weekend ticket for 22€.

– Important: Take a bag or backpack with you. I forgot to take one with me on Saturday and bought some books. You can imagine how annoying it is to carry the books that you have just bought in one hand while trying to view more books. Also, I recommend using a backpack because you will eventually go to the toilet, and the backpack is a good place to store your bought items.

– I focused on halls 3.0, 3.1, 4.0, 4.1 and 4.2. Each hall is divided in long stripes that are denoted alphabetically (A to L). What I did was I started from A and moved through all stripes till L. Needless to say that it is overwhelming. Basically, at some point I just tried to soak all the information through my eyes while looking left and right.

– Be prepared to walk slowly. In fact you have to because there are so many people. I found that I could switch the halls very quickly when I took the back escalators (not the front ones where all the people are).

– You can buy food at the book fair. From sandwiches to ice cream, everything is there. However, it is also expensive. I bought a sandwich for 3,20€ and a bottle of water for 2,70€ on Sunday.

– I bought two books from Tibia Press. At their booth they had these interesting looking books called infocomics. that explained things in a graphical way. The booth exhibitor then explained that they translated them from English, where the original name is “Introducing , a graphical guide”. I bought these two books:
1. Quantentheorie (quantum theory) and 2. Ökonomie (economy).

– There were at least 3 booths that sold special post cards with either a 3D look or moving effect. With the 3D look you had the the feeling that the objects had depth similar to a hologram. Have a look at this video showing a lenticular 3D postcard. The moving ones looked like this. I bought 5 postcards for 10 Euro.

– I saw Tim Mälzer (a famous German cook) cooking live.

– Alot of people in costumes (cosplayers) wearing crazy monster suits, dragon tails, swords, blue and pink dyed hair and makeup.

– There was this cool booth by the physicists from CERN reporting about the Higgs boson. One guy was a computer engineer who set up two kinect sensors orthogonally to capture your body. So, as you move between the kinect sensors you could see your 3D body shape on a projector screen.

– A demonstration of a 3D cyber classroom. We visitors had to wear polarized glasses to see the animation in 3D (similar to a cinema). The presenter showed us a realtime animated view of the human ear and explained how it works. The company that build the system is VISENSO. What I found interesting is that he used a wiimote motion plus controller for the presentation. This makes sense to keep the costs of the system low.

Smartboards which are electronic boards.

– The book fair closed at 18:30. I always forget how to get back to the subway U4. Just ask the information desk.

– At the end of the day my feet and legs hurt from standing and walking so long, but it was definitely worth.

Saturday, October 14:

– Although my legs were a little sore I went back to the book fair on Sunday, the last day.

– This time I went straight ahead to hall 3.0 and 3.1 to buy some piano books. I bought 3 books at the Schott booth (Klavier spielen – mein schönstes Hobby 1,2 and Die Zauberflöte: Ein deutsches Singspiel in zwei Akten. KV 620. Klavier. (Klassische Meisterwerke zum Kennenlernen)). Unfortunately, they didn’t have any bags left where I could put my 3 books. Fortunately, I learned from Saturday and brought my backpack with me.
– At the Schott booth they also had an iPad with a music note playing app. I can imagine this to be useful for sight reading.

– I looked at some of the eInk ebook readers.

– At the Brockhaus booth they had these books called Literaturcomics. These are comics that illustrate famous literature, e.g. Odysee, Hunchback of Notre-Dame, Don Quijote. The books looked really interesting.

– At the Franzis booth they had some educational material for people interested in electronics such as the Arduino learning package and a microcontroller.

– At 17:30 a woman announced on the speakers that the Frankfurter Buchmesse is closed upon which all visitors applauded. I love that moment because it remembers me that it was a great experience but it also makes me a little sad that it’s already over. I already look forward to the next year.

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Best LaTeX tutorial

Posted by Ed on October 6, 2012

This is the best LaTeX tutorial! Check it out:
LaTeX guide by artofproblemsolving

Another nice tutorial by tug india:
Latex primer
Online tutorials on LaTeX

There is also an excellent latex tutorial by Andrew Roberts.

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Tutorial: OOP in C++ (Part 2 – Class and object)

Posted by Ed on October 6, 2012

This is part 2 of the C++ Object Oriented Programming tutorial. Last time we focused on using multiple files. Today we will have a look at classes and objects.

1. Definition of a class

Consider this example: Albert Einstein, Frank Sinatra, Marie Curie, what do they have in common? Obviously, they are persons. We say they are objects of the class “Person”. In general, a class describes its objects by two things:
1. Attributes (properties)
2. Methods (functions that can access attributes and change them)

The Person class above may have the attributes “name” and “age”. We will give it the method “talk()” which allows our objects to actually talk.

Let’s write the Person class in C++:
– Create a new project in Codelite and call it “personClass” by right-clicking on the orange “Tutorial” folder from last time. Then double click the “personClass” folder to set the project as active.
– Open the “main.cpp” file in the yellow “src” folder and replace the code by:

#include <iostream>
#include <string>
using namespace std;

// definition of class "Person"
class Person{

	// attributes	
		string name;
		int age;
	// methods
		Person(string myName, int myAge){
			name = myName;
			age = myAge;

		void talk(){
			cout << "Hi! My name is " << name << " and I am " << age << " years old." << endl;
};   // <--- Don't forget the semicolon here!

// main() function
int main(){

	Person p("Homer", 42);    // Create an object of the class "Person"
	p.talk();                 // Let the object talk
	return 0;

– In line 07-24 we defined Read the rest of this entry »

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Tutorial: OOP in C++ (Part 1 – Multiple files)

Posted by Ed on October 3, 2012

This is part 1 of the tutorial on object oriented programming in C++. We will not begin with classes and objects right away. Instead we will focus on using multiple files first.

Other parts can be found here:
Part 2 – Class and object

1. First C++ program
To follow this tutorial you have to install C++ first. There are several ways. Here, I will assume that you have Codelite installed. So, run Codelite and do the following:

1. Create a new workspace
– Click on “Workspace” -> “New Workspace”. Type in “Tutorial” as Workspace name and confirm by clicking on the “Create” button.
– On the left hand side of Codelite there is a “Workspace” tab. Click on it. You can see the orange colored folder “Tutorial”.

2. Create a new project
– Rightclick on that orange “Tutorial” folder and click on “Create New Project”.
– Type in “helloWorld” as project name and click “OK”.
– On the left hand side, i.e. in the Workspace tab, you should see a folder “helloWorld”.
– Set the project as active: Either double click on the “helloWorld” folder or rightclick on it and choose “Set As Active”.
The active project will appear as green folder.

3. Code in main.cpp
– Left of the green “helloWorld” folder is a triangle. Click on it such that the yellow “src” folder appears.
– Click on the triangle left of the yellow “src” folder such that that you can see the “main.cpp” file.
– Double click on the main.cpp file. That file will already contain some code. Delete it and replace it with the following code:

#include <iostream>
using namespace std;

int main(){
	cout << "Hello World!" << endl;

	return 0;

4. Compile and run
– Compile the program by clicking Read the rest of this entry »

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