nigeodown downloads geomagnetic data for use with NICER software tools. The data are downloaded and installed automatically.
nigeodown is intended to run somewhat automatically so that users can use it with automated software scripts. Thus, there are no "ask" parameters, only hidden parameters with sensible defaults.
The 'infile' is the URL where the geomagnetic data are stored, as a gzipped tar archive file. The 'outdir' is where the unarchived geomagnetic FITS files should be installed.
The task tries to download the data with both the 'curl' and 'wget' programs. If both programs fail or are not accessible, the task will die with an error.
The task will create outdir if it is not already created. outdir should be writable by the user.
By default outdir=$GEOMAG_PATH, which means that the task will consult the GEOMAG_PATH environment variable. Users are encouraged to set this environment variable to the location where they will store geomagnetic data.
Download geomagnetic data to $HOME/geomag
export GEOMAG_PATH=$HOME/geomag nigeodownNote that users are encouraged to place the "export GEOMAG_PATH" statement in their .bashrc or equivalent.