mdspan VS conan-center-index

Why not use https://github.com/kokkos/mdspan though ?

It can be the base of whatever *you* write via bindings generators like pybind11. In that sense, the answer to your question is "however you like". For actual simulation code, you'll see a lot more legacy Fortran and C. That said, with things like mdspan maybe being standardized (proposal), efforts towards a standard linear algebra library, and the existence of ubiquitous HPC frameworks already having been written in C++, I would say it's only a matter of time before C++ accounts for an even bigger share of all HPC code.

I'm aware of only two relevant projects myself, I don't know much, came to reddit kind of by chance. One of the multi-dimensional array libraries proposed for potential standardisation, and a gnu machine learning library that was discontinued which could be worked off of. There's probably a lot more out there, but don't get distracted from making something awesome :)

As u/IyeOnline already made the important points about VLAs and std::vector, I would just add that you may find std::mdspan to be a helpful data structure. You can allocate 1d memory and give it a 2d shape of k with nice 2d indexing, eg auto& elem = mymdspan(row, col);.

Kokkos mdspan

The good thing here is that it heavily relies on mdpsan that is a multidimensional view that handle shape and strides. And kokkos provide a C++14 compatible implementation with a complete CUDA support.

Conan is a package manager for C/C++. See: https://conan.io/.

The way it works is that you can provide "recipes", which are Python scripts, that automate the process of collecting source code (usually from a remote Git repository, or a remote source tarball), patching it, making its dependencies and transitive dependencies available, building for specific platform and architecture (via any number of build systems), then packaging up and serving binaries. There's a lot of complexity involved.

Here are the two recipes I mentioned:

libcurl: https://github.com/conan-io/conan-center-index/blob/master/r...

OpenSSL v3: https://github.com/conan-io/conan-center-index/blob/master/r...

Now, for the sake of this thread I want to highlight three things here:

- Conan recipes are usually made by people unaffiliated with the libraries they're packaging;

- The recipes are fully Turing-complete, do a lot of work, have their own bugs - therefore they should really be treated as software comonents themselves, for the purpose of OSS clearing/supply chain verification, except as far as I know, nobody does it;

- The recipes can, and do, patch source code and build scripts. There's supporting infrastruture for this built into Conan, and of course one can also do it by brute-force search and replace. See e.g. ZLib recipe that does it both at the same time:

https://github.com/conan-io/conan-center-index/blob/7b0ac710... -- `_patch_sources` does both direct search-and-replace in source files, and applies the patches from https://github.com/conan-io/conan-center-index/tree/master/r....

Now, good luck keeping track of what's going on there.

Just checkout ConanCenter https://conan.io/center it's free.

https://github.com/conan-io/conan-center-index there's 200+ PR that need reviewing :) we add community reviewers fairly often

As for ffmpeg it was last updated 10 days ago https://github.com/conan-io/conan-center-index/commits/master/recipes/ffmpeg/all :)

This is a more complicated recipe https://github.com/conan-io/conan-center-index/blob/master/recipes/pcapplusplus/all/conanfile.py

You can use the Conan package manager with prebuilt binaries/libraries

https://conan.io/center

It's available in Conan too https://github.com/conan-io/conan-center-index/tree/master/recipes/crowcpp-crow though it's not well maintained so no promises if it's working

You need something like https://conan.io/center/ to install the dependencies. You're lucky because it works well with CMake.

This post on github contains a list of packages supported by conan 2.0, its also kept up to date https://github.com/conan-io/conan-center-index/discussions/16196

Use a package manager: https://vcpkg.link/ https://conan.io/center/