User:Gouzouni

A: An introduction

• Please describe yourself in three sentences, one of them regarding your current studies.
  • Which languages do you speak?
  • What's your overall background?

My name is Georgios Ouzounis . I am a fourth year undergraduate student in the School of Electrical and Computer Engineering in Aristotle University of Thessaloniki, Greece link (engineering bachelor includes 5 years of studies in my country). I love computer programming, mathematics and engineering and I hope to be able to stay involved with them through my whole life. My native language is Greek and I can also use English very well. As the title of my School indicates, my current field of study is Electrical and Computer Engineering involving subjects related to electrical and electronic circuits and also subjects related to computers and engineering such as control theory, analog and digital signal processing, computer networks etc...

• Why do you want to participate in the Summer of Code? What do you hope to gain by doing so?
  • Please also describe your previous experience with the SoC, if any.

My application for the Google Summer of Code 2014 on GNU Octave was rejected so applying on SOCIS is my second attempt on a program like this. Applying for participation in the Summer of Code in Space(SOCIS) is my first step towards real world software development. Until now I have been programming mainly for university projects so what I hope to gain from SOCIS is experience and knowledge on how to create software to be used by others.

• Why are you choosing Octave?

The past two years I had to deal with many university projects that required the use of software like Matlab or Octave. Using both of them I came to realize the power of such tools. That is the main reason why I chose Octave. I have actually wanted to contribute to Octave long before finding SOCIS but never found the nerve to try it until now.

C: Contact

• Please state the (unique and identical where possible) nick you use on IRC and any other communication channel related to Octave. We really want unique nicks.

• Which time zone do you live in? Will that change over SOCIS duration?

• Please state the timeframe (in UTC+0) when you feel most comfortable working during SOCIS. Where are your time buffers?

My nick in IRC, wiki.octave.org and the patch tracker is gouzouni (Gouzouni on the wiki). The time zone in my country is UTC+3 (Eastern European Time Zone) and this is not going to change during the whole SOCIS period. I usually code around 5.00 to 11.00 but time is not really a matter. Evenings are good as well!

Other contact informations are my e-mail geoconstructor625@gmail.com and my Facebook account Georgios Ouzounis. You can also find me in Skype under the name " Georgios Ouzounis ".

E: Coding experience

• Please describe your experience with C++, Octave or Matlab m-scripts, OpenGL and Qt.

I have been writing code in C and C++ for the last 4 years both for university projects and personal use. I have a very good understanding of these languages. I am well aware of the object oriented programming concept and I can use debuggers such as GDB well. As far as Octave m-scripts are concerned, I have been writing such code for the past 2 years mostly for university projects. I have written scripts for a wide spectrum of subjects such as optimization, image and signal processing, system recognition, control systems, machine learning and mathematics. I have very good knowledge of mathematics which helps in many ways such as writing vectorized code which is much faster than using loops. I have no experience using OpenGL or Qt.

• Please describe your experience with other programming languages.

Other programming languages that I use frequently and I am comfortable with are Java and Assembly. I have also used Python for some time. I am comfortable with using PThreads, Cuda and MPI and I am comfortable with parallel computing in languages such as Java, C++ and Matlab/Octave.

• Please describe your experience with being in a development team. Do you have experience working with open source or free projects?

I have no experience working with open source or free projects. I have good experience with being in a development team but only for small projects at the university, nothing as large as Octave.

• Please describe the biggest project you have written code for and what you learned by doing so. Also describe your role in that project over time.

The biggest project I have written code for is an Android application, a calculator, I developed last summer. It is about 2500-3000 lines of code. What I have mainly learned from that is if the small parts are well developed and documented then the big ones can be done quite easily. On the other hand, not being cautious in the first steps is going to be a big trouble on the later stages of a project. I was the only one working on that project so I had no specific role.

• Please state the commits and patches you already contributed to Octave.

Until now I have committed the patches #8379, #8383 and #8384. The first one includes the uencode and udecode functions of the signal package, the second one includes the peak2peak function of the signal package and the third one includes the shiftdata and unshiftdata functions of the signal package.

F: Feeling fine

• I am new to IRC but I have been using mailing lists for a while. I am also new to Mercurial and generally source code management systems. I have been using wiki sites before ( wikipedia and other ) but this is the first time I am modifying one. I am comfortable with make, gcc and gdb but I wouldn't say I am a master of the last one.

• I intent to stay in Octave's community after SOCIS is over no matter if I get picked to participate or not. I like programming and Octave's nature (mathematics, digital and analog signals etc...) is what I am comfortable working on. I would love to continue contributing.

O: Only out of interest

• My access to Matlab was(and still is) limited only inside the university campus so if I wanted to work my projects at home and not stay until late in the campus I had to use other software. That is how I found out about Octave two years ago. I have been using it for the last two years and another

reason why I want to contribute to it, is to help make it bigger. What gave me a hard time was the lack of a fullest symbolic package, that is why I want to work on it sometime after SOCIS.

• A thing that I had a little trouble finding an answer to how to contribute to Octave's development but I guess that was due to the fact that I had no idea what a source code management system is.

P: Prerequisites

• For the past year I have been using Ubuntu 13.10(13.04 before) and before that I used windows 8. I have both these operating systems installed

on my laptop and I have root access to both of them.

• I have a 24/7 access on an Internet connection, a computer and a computer with my progressing work on.

• I am free to install any new software on my laptop.

S: Self-assessment

• Please describe how useful criticism looks from your point of view as committing student.

After realizing that I was not born a good programmer (that was a long time ago :P ) I begun to appreciate any criticism. It's not that I like to be told that I am wrong, but if I am, I try my best to correct my mistakes.

• How autonomous are you when developing?

When I get a project on my hands I usually have a good deal of questions at first. Mostly clarification questions. After a while and when I get to understand what is actually needed I can say I am pretty autonomous both in working on the project and solving the new questions coming up. What I like though, is a frequent feedback on whether I am on the right course or not. I hate what some of my university professors do, giving me a project and meeting me again a month after to check on what level I am. I like a frequent, say every 3 or 4 days, communication with other members on the project or the mentor in order to check if everything is ok. It's the more frequent the contact is the better the outcome will be.

• Do you like to discuss changes intensively and not start coding until you know what you want to do?

My answer is yes, I do like to discuss changes intensively and not start coding until I know what I want to do. I don't expect to have everything figured out from the beginning but I like to have a decent schedule before starting writing code.

• Do you like to code a proof of concept to 'see how it turns out', modifying that and taking the risk of having work thrown away if it doesn't match what the project or original proponent had in mind?

Yes I do. I like to try many different ways of doing something in order to find the best. Since how will it turn out is not clear at the beginning, throwing work away, even if it is a week's work, is a risk I am willing to take.

Y: Your task

• The task I have chosen is the implementation of "High Precision Arithmetic Computation". The part that I would like to focus on would be the completion and test of the multi-precision class along with the implementation of several linear algebra algorithms which will support the use of multi-precision inputs.

• A rough estimated timeline for my work on the task would be :

Beginning until the end of first month ( June 1st - June 30th )

Include support for array and complex numbers on the already existent version of the multi-precision package.

Implement upclassing on operations involving objects of the multi-precision class.

Milestone 1 : End of first month : The goal at this moment will be to have a fully functioning multi-precision class, including array, complex number support and upclassing.

All deliverables will be tested and debugged during this period.

(July 1st - July 4th)

Testing, documentation, further debugging.

(July 5th - July 15th)

Break. As stated below, my examination period starts at June 10th and end at July 4th, so I would like to have a 10 days break in order to rest and clear up my mind.

( July 16th - August 15th )

Continue with the algorithms' development. Given the four days per algorithm estimation, about 7 - 8 different algorithms should be created during this period.

Milestone 2 : The goal for the end of this period will be to have a fully functioning multi-precision class ( or new basic numerical type ) and also a big enough arsenal of algorithms upon it.

(August 16th - August 31st)

Wrapping up the project. Finish what is left to be done. Documentation, debugging and testing.

A list of algorithms that will be implemented ( not necessary in this order ) to support multi-precision objects is given below :

Singular Value Decomposition ( SVD ), QR factorization, Cholesky factorization ( chol ), Inverse matrix computation, Eigenvalues and eigenvectors calculation, Solving linear systems, Root of non-linear function finder ( fzero ), Minimum value finder ( fmins ).

Development methodology

A rough schedule that will be followed ( not necessarily in this order ) while developing the above algorithms will be :

Step 1 : Check if there is some library based on GMP or MPFR implementing any of those algorithms and if this can be embedded on Octave.

Step 2 : Study Octave's already implemented for double precision algorithms and see if they can be re-formed in order to support multiple precision.

Step 3 : Check if there is any Fortran code implementing any of the required algorithms and if it can be used to add support for multiple precision.

Step 4 : Implementing the algorithm from the scratch. This will be the final choice, and will be done only if there is no other way to implement an algorithm.

Imponderables like illness, bad days, Internet going down globally and such stuff are considered by the above schedule, this is why a precise estimation of days per algorithm is not given.

The only commitment I have for the summer is my university exam period which starts at June 10th and ends at July 4th. Despite that, I will keep coding during these days for about 5 - 6 hours everyday as stated above. Studying for the exams will be done the other hours of the day.

N: News

I studied Octave's code for matrices and arrays and created the skeleton for adding matrix functionality on the multi-precision package. The skeleton was uploaded as a patch here 8429.

The matrix support for the multi-precision package is planned to be implemented by 2 classes.

1) MpvNDArray class, subclass of MArray<octave_mp>, implementing N-dimentional arrays of multiple precision objects ( octave_mp objects ).

2) octave_mpv_matrix class, subclass of octave_base_matrix<MpvNDArray>, implementing matrices of multiple precision objects.

The goal is to imitate the implementation of FloatNDArray and octave_float_matrix classes, and adjust it to work on multiple precision objects.