TIL (Today I Learned)

C++ Templates nested access

I just learned something cool about C++ templates you can set constraints based on the internals of a template parameter

Systemd mounts

On a modern linux system systemd has it own way to mount disks that superseed the traditional /etc/fstab method.

Python Abstract Classes

Today I learned that python has abstract classes. You can do something like:

Bash No History

Today I learned that if you add a space in front a command in bash, it will not be added to the history. Pretty neat! It is great when you have password or keys that you…

Numpy select

You can use numpy.select when you have multiple conditions to apply to an array. It works like a vectorized if/elif/else, which is very convenient.

LasPy to PDAL

First post of the new year … after spending way too much time writing a function that I didn’t need at the end :/

Marimo

I started to experiment with Marimo because I wanted to try a reactive notebook, that for basic data analysis seems an interesting idea.

Node commands additional arguments

To pass an argument to a node run command you need to add them after the -- separator.

Install Pytorch + Cuda using conda

You can install cuda in a conda enviroment using conda-forge and it just works :) No additional channels required.

Colorize point cloud: Polars vs PDAL

Here I am comparing polars and PDAL for adding a color information on a point clouds. Polars is reading a writing a point cloud transformed into parquet format. PDAL is…

Conda for R dependencies

On Linux conda CRAN doesn’t support binary packages, which means that you need to compile the packages from source. This works but is kind of slow and annoying. I have tried…

LasR and TLS

LasR is a great library but has been designed for ALS and while it can work with TLS data is far from optimised. What I found after some think is that the grid resolution of…

PDAL + python = use official bindings? not so fast!

when calling PDAL from python using the cli interface is often a better choice than using the python bindings

PDAL tindex append

when you run pdal create tindex it the file already exists (at least tested with gpkg) it will not overwrite it but append to it.

Laspy is over 2 times faster than PDAL at reading LAS files

Here you have a totally unscientific, but still interesting, benchmark made while I was waiting for pdal to finish, isn’t that a bit crazy that is so slow?

Coding with LLM and long output

For my development of the polars-qt package I have to work with a pretty long file that defines all units. I changed the API of my library to I needed to do a bulk update of…

Deploy Quarto on Github pages on a custom domain

For this website I wanted to publish it on a custom subdomain (til.mone27.net) and not on the default one (mone27.github.io). Doing this with quarto was slightly more…

HTTP Server behind remote ssh tunnel on windows = 💥

I want to run a local web server on my windows machine and this needs to accesible by the remote computer.

HTTPie.io

This is more a Today I Discoverved (Tid?) than Today I learned, but I discovered httpie which is an app to make manual http requests and is very neat. I only used the basic…