Boost your Octave (for MATLAB users)

Let’s face it, you are using Octave because MATLAB is too expensive for you. Maybe you’re not student anymore and got used to play with MATLAB, but now you need the best free alternative.

Certainly, if money is not a problem, MATLAB would overperform Octave in most of their characteristics (not all of them and I’ll show you) and is surely the best option.

Fear not! GNU Octave is here, and yes, it is indeed the best alternative to MATLAB, but… it’s not the same. We know, and here I present some useful tips to avoid any conflict with your migration to the Octave world.

Octave-logo Continue reading

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Kalman Filter – A painless approach

Needless to say but Kalman Filtering is one of the most powerful estimation processes in almost any Engineering field. From robotic vacuums to Satellite Guidance, it is everywhere. Here I will explain the how’s and why’s of the Kalman Filter (KF) in our lives.

keep-kalm-an-filter-7

Any decent technological project will use this robust method for the final estimation of the position of any intelligent system. The format of the given information can be, fortunately, represented as a Gaussian state.

Thanks to this property, it is possible to use Gaussian filters (KF is one of them), in order to improve the final estimation.

Gaussian modelling estimations are going to be carried in this explanation, so it is preferable to have this mathematical background (a simple understanding is enough) in order to follow the presented technique. Continue reading

VICE explores the hidden Mexico

I started to discover the most interesting stuff about Mexico when I left. I’m not gonna lie, I never realized what Mexico actually stands for until I saw the country as an outsider. In the same way, I got a closer perspective of the foreigner’s point of view.

It kinda surprises me and never found the words to express what Mexico is (within its thousands of faces). I think is better to show it, not just talk about it, but really put the culture, society and voices of the Mexicans in a visual way.

I have tried a couple of times (and will doing it as much as I can), but if a professional view of the culture is what people are looking for, then my biggest suggestion would be the VICE documentaries.

The first time I saw a VICE documentary about Mexico was the one about the “Mexican Pointy Boots“. I discovered that mexican fashion through VICE. I had never heard about it before. This is the kind of documentary that I like to see, closer to the people. It describes the real ‘feeling’ of the society, the thoughts of the Mexican people and in their own words.

Then I started to look more documentaries of the same style. What else could I discover from my country in this original journalistic enterprise? Well, there were more than expected, here a short list with some of my favorites, including the ones produced with the mexican beer brand “Indio”: Continue reading

And now… Bitcoins!

The concept of the Bitcoin is still a bit mysterious for me. The idea seems fair in a general view; however, the use of it is what worries me.

bitcoin-logo

Of course, when you’re using electronic means to do your transactions, you can always have a bug or something that suddenly fucks it up. I don’t want to rely my entire income in some virtual payment. Continue reading

A fancy visualization of planes intersecting – Part 3 (and Final)

The mystery is over! From the previous posts we have seen the way we can generate a random plane, and visualize 3 of them at the same time showing their intersecting point.

It might be enough for some simple visual purposes, but we are more ambitious than that and we want to get it fancier.planes intersecting

And that’s why I’m here! This final step would be to achieve a neat visualization of our three planes and even the equations involved. Let’s begin with what we have so far:

P = rand(3);
d = rand(3,1);
x = P\d;
hold on
drawPlane(P(1,:), d(1))
drawPlane(P(2,:), d(2))
drawPlane(P(3,:), d(3))
scatter3(x(1), x(2), x(3))

Where the function drawPlane was defined as:

function drawPlane(P, d)
[x, y] = meshgrid(-10:10);
z = -(1/P(3))*(P(1)*x + P(2)*y - d);
surf(x, y, z);

Continue reading

A fancy visualization of planes intersecting – Part 2

All right, I know I let you abandoned for a bit. But the last trip to Barcelona and the ongoing final exams in the University haven’t given me any chance to keep this. But I’m gonna take some minutes to finally write about the visualization of our planes.

In the last post we analyzed how a plane is constructed given the equation ax+by+cz = d. Then, given the parameters of this equation, I showed you how to generate its corresponding plane in Matlab.

Now I’m gonna keep this post short (sorry for the inconvenience), but here we are going to set 3 planes in a single visualization. In a third post, we’ll make all pretty and fancy.

planes intersecting

Continue reading

Humiliation of a Mexican child

Not new, still outrageous. A mexican inspector of the government did one of the most humiliating acts. But well, let’s start from the origin of all.

In Mexico are forbidden (among other things):

  1. Child labour.
  2. Selling cigarettes or alcohol to minors.

humkid01Clear so far? ok. However, there is a problem. It is not possible to achieve it. Why? Well, in Mexico there is a high level of poverty and many people have to find some source of income, rather than going even to schools, including children. True, some children are exploited and some others just don’t have any further goals in their lives. But, although the law is supposed to guarantee the same opportunities for everyone, in reality it is not possible due to the high inequality in the country. Continue reading