Add linalg documentation

.github/CODEOWNERS

@@ -1,4 +1,5 @@
 * @bcumming @msimberg @RMeli
-docs/software/sciapps/cp2k.md @abussy @RMeli
-docs/software/communication @msimberg
 docs/services/firecrest @jpdorsch @ekouts
+docs/software/communication @msimberg
+docs/software/prgenv/linalg.md @finkandreas @msimberg
+docs/software/sciapps/cp2k.md @abussy @RMeli

docs/software/prgenv/linalg.md

@@ -1,5 +1,81 @@
 [](){#ref-uenv-linalg}
 # linalg
 
-!!! todo
-    write some docs
+The `linalg` and `linalg-complex` uenvs are similar to the [`prgenv-gnu`][ref-uenv-prgenv-gnu] and [`prgenv-nvfortran`][ref-uenv-prgenv-nvfortran] uenvs in that they don't provide a specific application, but common libraries useful as a base for building other applications.
+They contain linear algebra and mesh partitioning libraries for a broad range of use cases.
+
+The two uenvs contain otherwise identical packages, except that `linalg-complex` contains `petsc` and `trilinos` with complex types enabled, but without the [`hypre`](https://packages.spack.io/package.html?name=hypre) package.
+`hypre` only supports double precision.
+See below for the full list of packages in each version of the uenv.
+Note that many of the packages available in `linalg` and `linalg-complex` are also available in [`prgenv-gnu`][ref-uenv-prgenv-gnu].
+
+## Versioning
+
+The uenvs are available in the following versions on the following systems:
+
+| version | node types | system |
+|-----------|-----------|--------|
+| 24.11 | gh200, zen2 | daint, eiger |
+
+=== "24.11"
+    In version 24.11, the common set of packages in both uenvs is:
+
+    * [arpack-ng](https://packages.spack.io/package.html?name=arpack-ng)
+    * [aws-ofi-nccl](https://packages.spack.io/package.html?name=aws-ofi-nccl)
+    * [blaspp](https://packages.spack.io/package.html?name=blaspp)
+    * [blt](https://packages.spack.io/package.html?name=blt)
+    * [boost](https://packages.spack.io/package.html?name=boost)
+    * [camp](https://packages.spack.io/package.html?name=camp)
+    * [cmake](https://packages.spack.io/package.html?name=cmake)
+    * [cuda](https://packages.spack.io/package.html?name=cuda)
+    * [dla-future-fortran](https://packages.spack.io/package.html?name=dla-future-fortran)
+    * [dla-future](https://packages.spack.io/package.html?name=dla-future)
+    * [eigen](https://packages.spack.io/package.html?name=eigen)
+    * [fftw](https://packages.spack.io/package.html?name=fftw)
+    * [fmt](https://packages.spack.io/package.html?name=fmt)
+    * [gsl](https://packages.spack.io/package.html?name=gsl)
+    * [hdf5](https://packages.spack.io/package.html?name=hdf5)
+    * [hwloc](https://packages.spack.io/package.html?name=hwloc)
+    * [kokkos-kernels](https://packages.spack.io/package.html?name=kokkos-kernels)
+    * [kokkos-tools](https://packages.spack.io/package.html?name=kokkos-tools)
+    * [kokkos](https://packages.spack.io/package.html?name=kokkos)
+    * [lapackpp](https://packages.spack.io/package.html?name=lapackpp)
+    * [libtree](https://packages.spack.io/package.html?name=libtree)
+    * [lua](https://packages.spack.io/package.html?name=lua)
+    * [lz4](https://packages.spack.io/package.html?name=lz4)
+    * [meson](https://packages.spack.io/package.html?name=meson)
+    * [metis](https://packages.spack.io/package.html?name=metis)
+    * [mimalloc](https://packages.spack.io/package.html?name=mimalloc)
+    * [mumps](https://packages.spack.io/package.html?name=mumps)
+    * [nccl-tests](https://packages.spack.io/package.html?name=nccl-tests)
+    * [nccl](https://packages.spack.io/package.html?name=nccl)
+    * [nco](https://packages.spack.io/package.html?name=nco)
+    * [netcdf-c](https://packages.spack.io/package.html?name=netcdf-c)
+    * [netlib-scalapack](https://packages.spack.io/package.html?name=netlib-scalapack)
+    * [ninja](https://packages.spack.io/package.html?name=ninja)
+    * [openblas](https://packages.spack.io/package.html?name=openblas)
+    * [osu-micro-benchmarks](https://packages.spack.io/package.html?name=osu-micro-benchmarks)
+    * [p4est](https://packages.spack.io/package.html?name=p4est)
+    * [papi](https://packages.spack.io/package.html?name=papi)
+    * [parmetis](https://packages.spack.io/package.html?name=parmetis)
+    * [petsc](https://packages.spack.io/package.html?name=petsc)
+    * [pika](https://packages.spack.io/package.html?name=pika)
+    * [python](https://packages.spack.io/package.html?name=python)
+    * [slepc](https://packages.spack.io/package.html?name=slepc)
+    * [spdlog](https://packages.spack.io/package.html?name=spdlog)
+    * [stdexec](https://packages.spack.io/package.html?name=stdexec)
+    * [suite-sparse](https://packages.spack.io/package.html?name=suite-sparse)
+    * [superlu-dist](https://packages.spack.io/package.html?name=superlu-dist)
+    * [superlu](https://packages.spack.io/package.html?name=superlu)
+    * [swig](https://packages.spack.io/package.html?name=swig)
+    * [trilinos](https://packages.spack.io/package.html?name=trilinos)
+    * [umpire](https://packages.spack.io/package.html?name=umpire)
+    * [whip](https://packages.spack.io/package.html?name=whip)
+    * [zlib-ng](https://packages.spack.io/package.html?name=zlib-ng)
+
+## How to use
+
+Using the `linalg` and `linalg-complex` uenvs is similar to `prgenv-gnu`.
+Like `prgenv-gnu`, the `linalg` and `linalg-complex` uenvs provide `default` and `modules` views.
+Please see [the `prgenv-gnu` documentation][ref-uenv-prgenv-gnu-how-to-use] for details on different ways of accessing the packages available in the uenv.
+You can for example load the `modules` view to see the exact versions of the packages available in the uenv.

docs/software/prgenv/prgenv-gnu.md

@@ -62,6 +62,7 @@ The release schedule is not fixed, with new versions will be released roughly ev
     * [[email protected]](https://packages.spack.io/package.html?name=superlu)
     * [[email protected]](https://packages.spack.io/package.html?name=zlib-ng)
 
+[](){#ref-uenv-prgenv-gnu-how-to-use}
 ## How to use
 
 The environment is designed as a fairly minimal set of