LaTeX started as an ASCII thing for English speaking nerds. Only later did people start to use it all over the word, in many languages from Cezch to Hindi. We now have XeTeX and LuaLaTeX. But like the serpent Sesha in the Hindu mythology, some of that early ASCII universe remains, notably in the BibTex […]
Category Archives: Tools
Climate Change Time Series Visualization with Polar Coordinates in R
This graphic appeared in social media lot in the last days I wondered how it would render on polar coordinates. So I made an R script to do so. The script is reusable for other data sources as I show below. So reuse, enjoy, and make useful. The plotting function Sea surface tempareature (SST) in […]
Text2Landscape: Visualize a Text in Multiple Spaces with R — Force-directed networks, Biofabric, Word Embeddings, Principal Component Analysis and Self-Organizing Maps
You will find no realistic landscapes prior to the Renaissance. The saints of medieval murals float in a conceptual space informed by hierarchies and symbolic relations; so do those of the Prajñāpāramitā Sūtras. The word “landscape” appears with the Dutch painters of the 15th century. A landscape is a part of the world perceived by […]
Execute SPARQL chunks in R Markdown
Coding in R is useless without interesting research questions; and even the best questions remain unanswered without data. RStudio provides a number of convenient ways to acces data, among which the possibility to write SQL code chunks in Rmarkdown, to run these chunks and to assign the value of the query result directly to a […]
Text Mining: Detect Strings: Word Lookup in a Large Corpus of Phrases Using a Large Dictionary with Julia
After achieving an optimized string detection algorithm in R for 1 milion phrases using a 200k large dictionary, I wondered if I can get better results in Julia. My first attempt at this was a catastrophe. Within 24 hours, the Julia community helped me to learn some basics of Julia code optimization and proposed a […]
Ideograph – explore ideologies of political parties with SPAQRL requests to WikiData, D3 and PixiJS.
Ideograph is a visual tool for exploring ideologies of political parties. It queries its data directly from the frequently updated WikiData graph database. You can filter the graph by country, and find further information by clicking on the node labels. Ideograph is licensed under GNU GPL 3.0. Presentation Video I’ve presented IdeoGraph at the Wikidata […]
Unify the extent of rasters in QGIS 3 to avoid clipping by raster calculator
This one drove me crazy today! If you try to sum values from rasters with different extent, the raster calcultor clips the result to their overlapping zone. This might make sense in most cases, but in many other cases it absolutely does not. Users should have a choice. An old workaround (2013) is proposed on […]
Reorder geom_bar or anything else in ggplot by the value of your choosing
You still find recent answers on StackOverflow counseling to redefine the factors of a data.frame to reorder elements of a ggplot graphic. In the 2020’s, this can be avoided. Factors are a heritage of a numerical focus of R, when text values were seen as an anomaly or, at best, as ordinal values. I highly […]
Scrape an image from DeepZoom with R and magick, recomposing a single image from multiple tiles
DeepZoom allows webmasters to display high resolution images in an online viewer. Among its users: The British Library The World Digital Library (WDL) Polona, the Polish Digital National Library BALaT, Belgian Art Links and Tools and many others DeepZoom mostly discourages downlading the original high resolution images to your local drive. This is how to […]
Les encarts dans QGIS
Pour qu’un personne ne connaissant pas la région que vous cartographiez puisse mieux s’orienter, il vaut la peine d’utiliser un encart, ce qui est possible dans le “print composer“. Il suffit, pour cela, d’ajouter deux cartes différentes. Lors de la création d’encarts, il est souvent pertinent de changer d’implantation. Pour identifier les bâtiments à l’échelle […]