Installation

See note for users of French supercomputing centers.

Dependencies

• max_diff_nc is written in Fortran (2003) and Bash so you need a Fortran compiler and Bash on your machine.

• Install the library NetCDF-Fortran, with the same Fortran compiler than the one you want to use for Max_diff_nc.

• CMake (version ≥ 3.17)¹.

Instructions

1. Get max_diff_nc from Github. As the Git repository contains a submodule, the easiest way is to type:

   git clone --recurse-submodules https://github.com/lguez/Max_diff_nc.git
   

   If you prefer to download a ZIP file then you will also have to download the cmake subdirectory.

2. Create a build subdirectory in the directory you have just downloaded:

   cd Max_diff_nc
   mkdir build
   cd build
   

3. Choose the installation directory CMAKE_INSTALL_PREFIX and type the command below with your choice after -DCMAKE_INSTALL_PREFIX= (enter an absolute path). The installation process will install a shell script, max_diff_nc.sh, in $CMAKE_INSTALL_PREFIX/bin. It is convenient for $CMAKE_INSTALL_PREFIX/bin to be in your PATH environment variable. For example:

   cmake .. -DFETCH=ON -DCMAKE_INSTALL_PREFIX=~/.local
   

4. Type:

   make install
   

You do not need to keep the downloaded directory Max_diff_nc (nor the build directory) after installation. Note that the installation process also installs a Fortran executable file, max_diff_nc, in $CMAKE_INSTALL_PREFIX/libexec. Do not remove this file.

Advanced instructions

• You can choose any name and any location for the build directory. You have to refer to the source directory when you run cmake from the build directory:

  mkdir /wherever/any/name
  cd /wherever/any/name
  cmake /where/I/downloaded/Max_diff_nc -DFETCH=ON -DCMAKE_INSTALL_PREFIX=~/.local
  

• The option -DFETCH=ON instructs CMake to download, compile and install the libraries NetCDF95 and Jumble. If you have already installed these libraries, you can omit the FETCH option.

Troubleshooting

If your installation of NetCDF-Fortran is in a non-standard location, and CMake does not find it, then re-run cmake setting the variable CMAKE_PREFIX_PATH to the directory containing it. CMake will then search ${CMAKE_PREFIX_PATH}/lib, ${CMAKE_PREFIX_PATH}/include, etc. For example:

cmake . -DCMAKE_PREFIX_PATH:PATH=/path/to/my/favorite/installation