Makefile options

1. Select compiler

Set a suitable compiler in the first line of the Makefile: COMPILER = <compiler_phrase>. The options are intel, gnu or portland - depending on your available compilers.

Table : List of default compilers

Compiler Option	Normal	With MPI
intel	ifort, icc	mpiifort, mpiicc
gnu	gfortran, gcc	mpif90, mpicc
portland	pgf95, pgcc	mpif90, mpicc

2. Select compiling options

• PRODRUN Set it to yes for production run, no for debugging.
• PRECISION Set it to ‘dble’ for double-precision calculations or to ‘sngl’ for single-precision calculations
• OUT_PREC Set it to ‘dble’ for double-precision in binary outputs or to ‘sngl’ for single precision
• DEBUG Set to yes to run in debugging mode. While running in debugging mode, set PRODRUN to no. The debug mode with intel compilers uses marmot90.
• USE_MPI Set to yes to use MPI
• USE_OMP Set to yes to use openmp (cannot work without MPI)
• USE_PRECOND Set to yes to perform some pre-conditioning of the matrices
• USE_FFTLIB This option lets you select the library you want to use for Fast Fourier Transforms. This can be set to JW, FFTW or MKL. JW refers to the inbuilt library by Johannes Wicht, while MKL refers to the Intel Math Kernel Library. Use JW if you don’t have Intel MKL installed.
• USE_DCTLIB This option lets you select the library you want to use for Discrete Cosine Transforms. This can be set to JW, FFTW or MKL.
• USE_LAPACKLIB This option allows you to select the library you want to use for LU factorisation. This can be set to JW, MKL, LIBFLAME or LAPACK.
• USE_SHTNS Set to yes to use SHTns library for spherical harmonics transforms. The helper script install-shtns.sh is available in the bin directory to help installing SHTns.

3. MPI_INCPATH

Make sure you set the path for your mpi header file mpif.h in MPI_INCPATH. The path depends on the computer. For PCs, this is commonly /usr/include or /usr/include/mpi. Use Open MPI for running MagIC on a PC. For computing clusters, please look through the documentation of the respective cluster for their MPI implementation.

4. Other compilers

If your available compilers are different from the options provided in the Makefile, then change them suitably using the options COMP_FC and COMP_CC for serial fortran and C compilers and COMP_MPFC and COMP_MPCC for compilers with mpi implementation.