Porting Scientific and Engineering Programs to Linux

A free collection of routines written in FORTRAN 77 is SLATEC. This collection includes over 1400 mathematical and statistical subroutines that are very well documented with comment lines in a standard format at the head of each piece of source code. In order for this collection to be efficiently used by a work group sharing a workstation, it was found that the creation of a library archive was most appropriate. The more, head, and grep commands with some occasional awking have proven most adequate for finding the subroutine desired and reviewing the documentation integrated in the source code collection.

The SLATEC Version 4.1 library was complied and created using g77 under Linux, and none of the sources required patching. There is one hitch: some of the routines call user supplied subroutines, and therefore, cannot be included in the library. These routines are bvder, bvpor, bvsup, dbvder, dbvpor, dbvsup, dexbvp, drkfab, exbvp and rkfab. The library was created by placing the script in Listing 3 along with all of the .f sources in the directory /usr/local/src/slatec and executing the script.

Listing 3

The resulting library, libslatec.a, is placed in /usr/local/lib and can be accessed at compile time by any user, assuming /usr/local/lib is in their library path, with a command like:

g77 -o somefile somefile.f -lslatec

We have demonstrated that with a little work g77 can be used to compile very significant FORTRAN code packages. With the addition of two simple C routines, g77 was used to compile MCNP, and with no source code modification at all, it compiled the vast mathematical source collection know as SLATEC. g77 has proven to be a FORTRAN compiler that can truly make Linux on Intel hardware, a workstation option for the engineer and scientist, especially one on a budget.

More information about Charles' and Gary's computational endeavors is available at www.csn.net/~ckelsey.