@sepdek's

Analysis of (time-series) data being collected in (near) realtime often provides insight for a process underway. As the current situation with COVID-19 is still critical lots of data are being collected, curated and streamed throughout the world, and researchers strive to get the most out of them to identify patterns and, maybe, make predictions. In […]

Clustering is an important category of machine learning methods and a main form of unsupervised learning. Clustering is essentially distinctive and substantially different from the other dominant form of machine learning, classification, in that it does not rely on training (supervised learning). In principle, clustering represents any method that tries to identify and distinguish groups […]

Of the most basic forms of a machine learning system based on neural networks is the one in which training is accomplished using back error propagation, or simply back-propagation. Back-propagation is a technique, like many others, that targets the minimisation of a cost function during a learning process by following the descending gradient of the […]

Machine learning is a research domain that is becoming the holy grail of data science towards the modelling and solution of science and engineering problems. I have already witnessed researchers proposing solutions to problems out of their area of expertise using machine learning methods, basing their approach on the success of modern machine learning algorithm […]

This post serves as a practical approach towards a vectorized implementation of the Expectation Maximization (EM) algorithm mainly for MATLAB or OCTAVE applications. EM is a really powerful and elegant method for finding maximum likelihood solutions in cases where the hypothesis involves a gaussian mixture model and latent variables. Introduction EM is connected with the […]

A straightforward approach to do geometric image transformations using MATLAB is to take advantage of the imtransform function available. First the image is supposed to be within a ‘unity’ rectangle and initial transformation conditions are defined accordingly: udata = [0 1]; vdata = [0 1]; fill_color = 128; org_rect = [0 0;1 0;1 1;0 1]; […]

Recently I read an interesting book “The Grand Design” by Stephen Hawking and Leonard Mlodinow. Somewhere at the end of the book there was a reference to the well known game of life by John Conway (1970). Although I knew it was implemented by various researchers and is already available in MATLAB with a demo […]

In a recently posted question @StackOverflow a user asked how to find the maximum Euclidean distance in a binary image produced by Canny edge detection using MATLAB. The original post is here. I report my response here just for archival purposes. Provided that you have a binary edge image, you need to think of white […]