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From: ajayshah@aludra.usc.edu (Ajay Shah)
Newsgroups: comp.lang.fortran
Subject: Fortran (LONG, you may think it's religious.)
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Date: 27 Jul 90 05:38:22 GMT
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(LONG!)

I saw a huge number of postings citing one or the other reason
given which Fortran is the best computing solution around.  I'll
describe one experience here.. see what you think of it.

I started life writing fortran since the first course in
programming at school (IIT, Bombay, India) taught fortran-77.  
They had a great home-made compiler (gee, how I loved it) which 
did things like trap uninitialised variables and scream about 
wrong number or type of parameters, so it was a great place to 
start off programming.  I fell in love with computers at first 
sight; and wrote something like 10k lines of fortran within those 
three months.  You can say I know fortran intimately.

I learned pascal that december (fortran was the
fall semester), because everybody I knew who'd tried pascal had
never come back, and got hooked on serious data structures.
Later, of course, with turbo pascal, there was no turning back;
it was not just the superiority of language but also the lovely
environment.

Last year, I joined the RAND corporation where my research group
lives on large-scale maximum likelihood.  On all three relevant 
fronts: size of datasets, dimensions of parameter vector and
complexity of likelihood function, our work is cutting edge. 
Before I arrived, every single job was done with a monolithic
fortran program.

FACT 1:
	Just for kix, I wrote a maximum likelihood package one
	night in Turbo Pascal.  It took a week to make it totally
	slick.  My program is far more comfortable to use than the
	fortran programs used at RAND, and does more in terms of
	statistical computations supported.  I used the Turbo
	Numerical Methods toolbox; it had all the basic routines I
	needed, I only had to write a few routines related to the
	normal distribution by hand where I hand-translated public-
	domain ratfor code.

	I might be brilliant, but writing this in a week was
	tremendous.  I don't know of any experience where writing a
	full MLE system in fortran has not taken a few months
	atleast, this has to do (in a deep sense) with the clumsy data
	structures and abstraction supported by fortran.  

	The fortran system is around 10k lines, the pascal is 3k
	lines.  I don't think these numbers are easily shrugged
	off.

A lot of people doing scientific programming live in a daze where
mainstream computer science is for every other kind of
programming in the world; *they* only need to write fortran
programs without intelligence in data structures, etc.  I think
that attitude is a sad mistake.  Personally, I've found
tremendous gains in complexity control through "smart" data structures"
in every single program i've written.


FACT 2:

	In the work I've done at RAND ever since, while I've not
	been able to get my group off fortran, I've transformed the
	character of computing with fortran using Unix tools.  I
	recently wrote a simulator where dynamic programming
	problems are solved.  The traditional fortran programer
	would have written one monolithic program which did the
	simulations, with some lousy interface.  Instead, I have a 
	solution involving 
	
		a 150 line cshell script, 
		2 awk programs, one 100 lines and the other 50 lines,
		one fortran program of 300 lines.

	The first awk program parses a very convenient input file
	and generates a cshell script whose
	output is converted by the 2nd awk program into a gnuplot
	script.

My grouse with the "fortran-style-programmer" lies in the way he
takes fortran to be the black-box solution to every computing
problem.  There is something so myopic there, it really gets me
irritated talking with such a specimen.  Instead of thinking in
terms of a huge space of possibilities where fortran programs are
one (pretty limited) option, there is the mentality of
approaching everything as a fortran program.
-- 
_______________________________________________________________________________
Ajay Shah, (213)747-9991, ajayshah@usc.edu
                              The more things change, the more they stay insane.
_______________________________________________________________________________
_______________________________________________________________________________
Ajay Shah, (213)747-9991, ajayshah@usc.edu
                              The more things change, the more they stay insane.
_______________________________________________________________________________