Hello! I'm trying to use a subprogram from the Starlink Project - Lucy in the library KAPPA - that is already installed and compiled. The idea is to be able to call it from my fortran routine. Something like this: Code (Text): PROGRAM ex INTEGER i REAL in(10),psf(10),out(10) DO i =1,10 in(i) = rand() psf(i) = rand() ENDDO lucy in psf out WRITE(*,*)out END Is that possible? If so, how should I compile the file (using gfortran)? After downloading and unpacking the Starlink package you write in the terminal: $ export STARLINK_DIR=$HOME/Astronomy/Software/star-2015A $ source $STARLINK_DIR/etc/profile After that you can run the subprograms by typing: $ kappa $ lucy The compiled lucy file can be found here: $HOME/Astronomy/Software/star-2015A/bin/kappa/lucy The source file lucy.f can be found here: https://github.com/Starlink/starlink/blob/master/applications/kappa/libkappa/lucy.f Many thanks in advance!