sepdek March 25, 2020

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 […]

sepdek February 16, 2018

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 […]

sepdek January 23, 2018

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 […]

sepdek March 14, 2014

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]; […]

sepdek February 16, 2014

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 […]

sepdek February 10, 2014

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 […]