Hi. I have a code written in single-precision (MIEV0.f by Wiscombe). I want to compile and run it in double-precision. Is there some compiler options in gfortran ? (in g77 ? (if I will have to use old computer)) In case the answer is 'no', is the following sufficient: 1) change 'REAL' type to 'DOUBLE PRECISION' globally in the code. 2) change all calls to 'REAL(..)' function by 'DBLE(..)'. Thank you. Regards, Dima.