FORTRAN program to extracting column

Dear folks

I have a large data set which contains 400K columns. I decide to select 50K determined columns from the whole 400K columns. Is there any suggested fortran program which could do this process for me? I need to also mention that I store all of the columns id in one file which may help to select those columns out of the whole 400K columns.

Regards
Saj

Moderator comments were removed during original forum migration.