Downloading the code

Downloading the code#

The next step after installed these libraries and packages is to get the DALES code. The example below uses the Git software for this purpose. After going to the destination path on your system, download the code by using the command below

<username> <currentpath> % git clone https://github.com/dalesteam/dales.git

Here, a new directory called dales should have appeared. By default, the latest main branch is checked out inside this directory (denoted by the *). This can be confirmed by doing the following

cd dales
git branch

which should give as output

 * main

Other available branches of the main repository can be viewed with the -a option

<username> dales % git branch -a
* main
remotes/origin/3.1
remotes/origin/3.2
remotes/origin/4.1
remotes/origin/4.1_TROFFEEhack
remotes/origin/4.1_aero_m7
...

Checking out a specific branch (e.g., the ruisdael branch) is done via

git checkout -b <newname> remotes/origin/ruisdael

Initialize submodules#

This step is required to fetch some external libraries, e.g. RRTMG and RRTMGP.

git submodule init
git submodule update

Planning on coding yourself in DALES?#

If you plan to change parts of the code and want to keep track of your changes, it may be worthwhile to use your personal Github account and first fork the main repository. The steps to get the code on your system are then slightly different.

git remote add origin https://github.com/<your_account>/dales.git
git remote add upstream https://github.com/dalesteam/dales.git

git config --global user.name "YOUR NAME"
git config checkout.defaultRemote origin

git fetch --all

git checkout -b main origin/main

Note

This option will checkout the code in your current directory, without first making a separate dales destination directory.

Compilation of DALES#

Generic compilation#

The next step after obtaining the code and installing required dependencies, is to build the code. As a starting point, we assume you are still in the main dales directory after checking out the main branch via git. It is advised the build the code in a different folder to better maintain overview. We therefore first move one directory up, make a new directory and move into that directory.

cd ../
mkdir build
cd build

We then invoke cmake on the directory where the code is placed. This will configure the build of the code.

cmake ../dales

Finally, the code can be build with the following command:

make

After successfull compilation, the executable dales is located in the subdirectory bin/. Compilation of the code may be sped up using the -j <nprocs> specifier, with nprocs being the amount of parallel processes.

Compilation options#

It is possible to specify optional features at the compilation stage of the model. These optional features can be activated by adding them as specifyers to the cmake command. CMake options are specified as -D<option>=<value>. For example:

cmake ../dales -DCMAKE_BUILD_TYPE=Debug

will produce a debug build. The debug build is much slower than the release build but contains more error checks. A list of commonly used options is given below.

Option	Description	Allowed values	Default
`-DENABLE_FFTW`	Build with FFTW	True/False	True
`-DENABLE_HYPRE`	Build with HYPRE	True/False	False
`-DENABLE_FP32_FIELDS`	Use single precision floating-point numbers for prognostic fields (momentum, temperature, etc.)	True/False	False
`-DENABLE_FP32_POIS`	Use single precision floating-point numbers for the Poisson solver	True/False	False
`-DENABLE_ACC`	Build with GPU support through OpenACC	True/False	False

Caution

To use HYPRE or FFTW, the library needs to both be enabled at compilation and selected at runtime by setting the &SOLVER section of the namoptions input file. See Alternative Poisson solvers (Wiki). By default, FFTW is used if the library was found at compilation.

Hint

-DPOIS_PRECISION=32 and -DUSE_HYPRE=True can be used together, but HYPRE is 64-bit only, so only use this, if it is really what you want.

Compilation on specific clusters#

Delftblue (TUDelft HPC)#

Tested 20-11-2023

module load 2023r1-gcc11
module load openmpi/4.1.4
module load cmake/3.24.3
module load netcdf-fortran/4.6.0
module load fftw/3.3.10

git clone https://github.com/dalesteam/dales

# for dev branch:
git checkout dev
git submodule init
git submodule update


cd dales
mkdir build
cd build

export SYST=gnu-fast
cmake ..  -DUSE_FFTW=True

make -j 8

Snellius (Dutch National system)#

Tested with module set 2023

module load 2023
module load foss/2023a
module load netCDF-Fortran/4.6.1-gompi-2023a
module load CMake/3.26.3-GCCcore-12.3.0
# module load Hypre/2.29.0-foss-2023a

mkdir build
cd build
export SYST=gnu-fast
cmake ..

# or, for single precision (options for version >= 5.0 or dev):
# cmake ../dales -DENABLE_FP32_FIELDS=ON -DENABLE_FP32_POIS=ON

make -j 8