Tux Machines

Programming Leftovers

Posted by Roy Schestowitz on Aug 17, 2024

Dirk Eddelbuettel ☛ RcppEigen 0.3.4.0.1 on CRAN: Minor Maintenance

A new maintenance release of RcppEigen is now on CRAN, and will go to Debian shortly as usual. Eigen is a C++ template library for linear algebra: matrices, vectors, numerical solvers, and related algorithms.

A very recent change in the development version of R (aka “r-devel”) expanded the set of declared BLAS and LAPACK functions (and I tooted approvingly about it as well). It turns out that the xerbla() declaration there (which, as usual for R and as discussed in Writing R Extensions, defines the new optional character length entry for a char vector) conflicts with one in the blas.h header in Eigen upsetting the compilation of just one reverse-dependency. So CRAN, as they so often (and quietly) do in these cases, gave us a friendly and concise heads-up and asked for a change so we complied, did the usual reverse-dependency check of the other 400+ packages using RcppEigen and produced the new release which was injected into the repository during the current summer break.

Rlang ☛ Mastering grepl with Multiple Patterns in Base R

Hello, fellow useRs! Today, we’re going to expand on previous uses of the grepl() function where we looked for a single pattern and move onto to a search for multiple patterns within strings. Whether you’re cleaning data, conducting text analysis, grepl can be your go-to tool. Let’s break down the syntax, offer a practical example, and guide you on a path to proficiency.

Rob Knight ☛ Building a Seating Plan for Relay 10

The first step was to recreate the seating chart for the Hackney Empire. I could have hard-coded this but I really didn't want to so I created an object for every section (stalls, dress circle, upper circle). The widest part of the stalls is 48 seats (24 each side) but every row has a different amount of seats so I started with the following, then mapped over each row to add the "ghost" seats either side:

Roman Kashitsyn ☛ Transaction models are programming paradigms

This article explores the differences between the account and utxo transaction models, which are surprisingly similar to distinctions between programming styles. Account-based chains model computation using the object-oriented style, where each update touches the global ledger state, while utxo-based chains employ functional style with substructural typing. The benefits and downsides of each model mirror those of the corresponding programming styles.

Perl / Raku

Linux Links ☛ 10 Best Free and Open Source Perl Static Site Generators

To provide an insight into the quality of software that is available, we have compiled a list of the best Perl static site generators.