Compilers/Linkers

These are the codes that convert your instructions into executable codes.

Watfor

                I give a diskette labeled W4 to those who take my class.  This contains both a copy of the University of Florida licensed Watfor which is an old Dos code limited to 640 K in size and the locally developed gplot code.  Contact me if you need such a diskette. This is more than a little obsolete, but it is still the easiest and most complete debugger that I have ever found. As it runs it informs you of each and every “uninitialized” variable. These are usually typo's. It tells exactly where in the source that they occur making them very easy to fix.

Simple directions are in Watfor.doc .htm.  Advanced Watfor features are covered in Wsystem.doc .htm and a description of the plotting codes is in gplot\WELCOME.      

Watcom

Watfor is adequate for the class, but those doing research will probably want to use the full power of their computer.  Watcom developed much better code before its bankruptcy.  This was picked up and developed as open source code by SciTech Software, Inc.  It is available from

http://www.openwatcom.org.  The installation produces a set of helps that include most of the Fortran instructions needed to run code.  It also has a IDE that enables the users to set up codes in paths in a fairly intuitive way.  There are some details on this in openwatcom.htm.  Watcom has extended f77 to include a number of Fortran 90 features.  The most important of these is dynamic array allocation.  Unfortunately they do this in an easier way than the standard so that minor modification is needed to give code than can be compiled by Fortran 90 compilers. 

            If you include C in the download and setup, the same ide and editors work for C and for mixing C and Fortran.  There are also helps for C and for mixing C and Fortran.

g77

                http://www.mbr-pwrc.usgs.gov/software/g77.html contains a zip and a few directions for the Free Software Foundation version of Fortran 77 (windows, but runs in a dos window).  This is the compiler found by default on most linux systems.   This compiler converts code to C and then compiles the C.  It adheres very closely to the ansi 77 standard.  It is relatively easy to mix C and Fortran with this compiler.  gcc code can be found at http://www.delorie.com/djgpp.  It is much more complicated to install, but includes an IDE.  The file FreeFortran\startg77.txt needs to be copied to a folder in the path set up by the command prompt and renamed startg77.bat.  In my case this is c:\watcom\binnt so that this file is simply save into this folder.  Then the command to ready the system for g77 is

>startg77.bat

Complilation to an object file then is

>g77 –c test.for

To the executable a.exe, the command is

>g77 test.for

gfortran

                http://gcc.gnu.org/wiki/GFortranBinaries is the Free Software Foundation version of Fortran 90.  Among other improvements this adds the ability to dynamically allocate variables.  It runs in windows and most other systems including the newest mac’s.  The free software download for windows is a self extracting binary that changes the default path setting so that the command to produce a.exe is

>gfortran test.for

intel

            http://software.intel.com/en-us/articles/non-commercial-software-download/

The Linux version of Intel’s Fortran 90 is free for non-commercial, non-academic users.  The Linux version is command line driven.  This software includes quadruple precision, some of which is used to dramatically increase the dynamic range of the variables.  The windows version uses Microsoft Visual Studio 2005 as its IDE.  I liked it so much that I bought it, at a negotiated academic price.  I normally use it from “Microsoft Visual Studio”.  The command line version requires a setup FreeFortran\STARTI-10.txt that needs to be placed as a bat file in a folder in the normal startup path.

>startI-10

>ifort test.for

-out:test.exe

            This last is the executable.

Pascal

“Thus, even after C, C++, and Java took over the programming world, Pascal retains a niche in the market. Many small-scale freeware, shareware, and open-source programs are written in Pascal/Delphi. So enjoy learning it while it lasts. It's a great introduction to computer programming. It's not scary like C, dangerous like C++, or abstract like Java. In another twenty years, you'll be one of the few computer programmers to know and appreciate Pascal. “[1]

                http://freepascal.org/ and http://wiki.lazarus.freepascal.org.  I use Delphi5 in windows and fpc in linux/fedora. 

fpc –Mdelphi code.dpr

The Lazarus editor resembles that of Delphi and has very good diagnostics.  I installed these on my linux machine as described in yum-Pascal.txt.  Pascal is fast and has a 10 byte extended precision option that is one of the easiest and fastest ways of improving precision.  The extra precision gives an extra factor of 100 tolerance for linear dependency in curve fitting MatrixInverse\Cholesky\Singular.doc .htm.  The spectrum analysis code Cambio ..\Fittery\robfit\Welcome.htm  is among the codes described by Tao Yue in the quote from the introroduction to his tutorial above. 

http://freepascal.org/docs.var - contains instructions on Pascal including the tutorial by Tao Yue.  I found a Turbo Pascal by Walter J. Savitch[2] to be the most useful of the various manuals.