Variable Scope: Memory Spaces in Matlab

Every variable has a scope or is it the opposite? - Source: Image

Every variable has a scope or is it the opposite? – Source: Image

For this post, we are glad to welcome Nicholas as a contributor to If you are interested in writing a guest post, please don’t hesitate to contact us

In this post, we talk about variables. In particular, we will explain where variables “sit” in memory depending on where you declared it (within a script or a function). This is a very important post if you are learning the language.

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Posted in Beginners, Learning Matlab | 1 Comment

Happy new 2015

Happy new year coding in 2015 - Source : Image

Happy new year coding in 2015 – Source : Image

It is an established tradition that blogs will look back on new year and discuss past achievements. I also felt it was a good opportunity to share with you some results from this website statistics and suggest what the next year will be like.

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Posted in Various | 1 Comment

Auto-contrast: an optimization example where Matlab beats Matlab


An auto shown in high contrast – Source : Image

For this post, we are glad to have Thierry as a guest blogger. He talks about an optimisation example he recently encountered that is a good indirect example of ‘inlining‘.

As my first post here, I will first describe a standard “auto-contrast” method with some optimizing hints. I will then try a more powerful one, and hit a situation where the buit-in Matlab function (quantile) can be beaten by a simple Matlab script.

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Posted in Optimizing your code | Tagged , , | Leave a comment

Debugging in Matlab

The first reported bug - Source : Wikipedia

The first reported bug – Source : Wikipedia

You’ve just finished writing your latest and greatest Matlab program. You’re sure this program will solve all the world’s (or at the very least all of your) problems. Just as you run your program, you see the dreaded red error text. Looks like it’s time to do some debugging! In this post, I’m going to take you through some of the common types of errors you will see when developing your software and how to solve those problems. Of course, when you’re first starting out in Matlab, these errors seem a bit cryptic and can take some time to solve. After just a bit of practice, though, you will soon be able to quickly spot and correct your errors.

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Posted in Beginners | 3 Comments

Logical operations and logical indexing in Matlab

Nerd of all countries, standout! Source : Image

Nerd of all countries, stand up! Source : Image

In this post, we talk about logical operations but also how to use your Matlab skills to analyze your shopping expenses (Yes, we are all absolute nerds and love it).

You will learn how to use logical operations to search large data matrix very quickly. If you have never used logical operators in Matlab, this is a MUST-READ! Continue reading

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How and when to convert between data types

Using the right data type is an act of wisdom - Source : Image

Confucius : Do not use a cannon to kill a mosquito – Source : Image

In this post, we talk about data types and extend on our previous post on the matter. You will learn how to convert between them but more importantly when and why you should consider such things.

As often, we delve into more advanced examples of data conversion that will be of interest to a large audience.  Continue reading

Posted in Beginners | 2 Comments

ICA demystified

Demystifying the black box

Demystifying the ICA black box – Source : Image

This post has been on the back of my mind for quite some time, ever since I wrote about Principal Component Analysis. Independent Component Analysis or ICA is an algorithm to extract underlying structure hidden in multi-dimensional datasets. As for PCA, It is fairly ubiquitous (including in Neuroscience). However, as opposed to PCA, getting an intuitive understanding of ICA is much harder and many persons use it as a magic black box (no offense, I have been there too). I won’t provide comments on any code as fastICA is already freely available in Matlab. My hope here is to facilitate the understanding of what ICA is and how it works.  Continue reading

Posted in Intermediate | 1 Comment