Quantifying the composition of substances in geosciences, such as the mineral composition of a rock in thin sections, or the amount of charcoal in sieved sediment samples, is facilitated by the use of image processing methods. Thresholding provides a simple solution to segmenting objects within an image that have different coloration or grayscale values. As an example we use thresholding to separate the dark charcoal particles and count the pixels of these particles after segmentation. Continue reading “Quantifying Charcoal in Microscope Images Using MATLAB, Part 2”
Adaptive Filters in Paleoclimatology – the Python Version
Paleoclimate time series are often very noisy due to the combined effect of low sedimentation rates, intensive bioturbation and small sample sizes (5-20 foraminifers). Adaptive filters may help to increase the signal-to-noise ratio of such time series where conventional methods such as fixed filters cannot be applied if optimal filtering is to be achieved, because the signal-to-noise ratio is unknown and varies with time. Continue reading “Adaptive Filters in Paleoclimatology – the Python Version”
Analyzing Climate Transitions with MATLAB
Detecting, measuring and classifying transitions in climate time series is one of the most important applications in modern time series analysis (Mudelsee, 2000; Trauth et al., 2018, 2021). Three methods are presented here: sigmoid fit, ramp fit and change point detection. Continue reading “Analyzing Climate Transitions with MATLAB”
Creating a Map with Coastlines and Topo Contours with MATLAB
Variants of a map of northeastern Africa appear in recent publications (e.g., Trauth et al., 2021a, b) using coastlines from the GSHHG data set and topography from the ETOPO1 data set. Here I show how it was made. Continue reading “Creating a Map with Coastlines and Topo Contours with MATLAB”
Creating a Bubble Chart Animation with MATLAB
We wanted to display pulsating circles on a map and save the result in a video. Here is part one, the pulsating circles. The map will come in the next post.
Continue reading “Creating a Bubble Chart Animation with MATLAB”
56th Online Shortcourse on MATLAB & Python Recipes for Earth Sciences
The popular online course on data analysis in the geosciences will be taught bilingual for the first time, using the two leading programming languages and development environments MATLAB and Python in parallel on 18–22 September 2023. The course is based on the 5th edition of my books MATLAB Recipes for Earth Science (Springer 2021) and Python Recipes for Earth Sciences (Springer 2022).
Continue reading “56th Online Shortcourse on MATLAB & Python Recipes for Earth Sciences”
Online Courses in Modern Data Analysis Methods in Earth Sciences with Python and MATLAB
Nearly 30 years ago, I began teaching compact courses on data analysis in the earth sciences. Almost 20 years ago, I started thinking about writing textbooks. Now there are five textbooks and many different course formats for you. Here is an overview of the current options! Continue reading “Online Courses in Modern Data Analysis Methods in Earth Sciences with Python and MATLAB”
MATLAB Example to Illustrate John Aitchison’s Log-Ratio Transformation, Part 3
A while back I wrote a post about John Aitchison’s Log-Ratio Transformation, Part 1, in the time domain and today Part 2 in the frequency domain. Here’s Part 3 with a MATLAB demonstration of a nice Aitchison example presented in an extended abstract by Pawlowsky-Glahn and Egozcue (2013). Continue reading “MATLAB Example to Illustrate John Aitchison’s Log-Ratio Transformation, Part 3”