Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.csd.uwm.edu!bionet!ig!arizona!gudeman
From: gudeman@arizona.edu (David Gudeman)
Newsgroups: comp.lang.misc
Subject: Non-professional programmers (was: Which language to teach first?)
Message-ID: <13380@megaron.arizona.edu>
Date: 22 Aug 89 00:21:21 GMT
Organization: U of Arizona CS Dept, Tucson
Lines: 51

In article  <9015@june.cs.washington.edu> kolding@june.cs.washington.edu (Eric Koldinger) writes:
>...
>Why?  Just because someone doesn't want to be a CS major doesn't mean that
>he/she doesn't want to learn to program, or have need to program.  What about,
>for instance, engineering majors who often have to design large programs, but
>aren't CS people, per se?

You know a few years ago, I wouldn't have even noticed that last
sentence.  Since then I've had occasion to read a lot of code that
wasn't written by Kernighan and Richie or other high-quality
professionals, and have been appalled at how bad programming is out
there.  I have also had occasion to teach programming, and was
surprised to find out how hard it seems to be for a lot of people.
They just can't seem to grasp the concepts of modularity, reusability,
maintainability, internal documentation, or simple elegance.  I guess
it's been so long since I went through that stuff, that I don't
remember what a trial it was to learn.

Perhaps more important is the idea of using efficient data structures
and algorithms.  I've seen functions consisting of nothing but a huge
switch statement:

  switch (i) {
  case 0: return "0";
  case 1: return "1";
  case 2: return "2";
  ...

where the constraints on i clearly allowed the use of an array instead.

I've had a discussion where I pointed out to someone how to turn a
O(n^2) algorithm into a O(n) algorithm with the same constant factor,
and he said it was a clever hack, but not worth implementing because
"computers are getting faster all the time."  He had been complaining
about the speed of the O(n^2) algorithm, but he didn't seem to believe
there would be much difference.

I've seen a set of functions for handling linked lists, that all use
the same global variable for list traversals.

This has brought me to the conclusion that the era of non-professional
programmers has past.  The programming discipline has advanced to the
point where it really does take four (or more) years of in-depth study
to become competitive in the field.  Would you expect an electrical
engineer to design a car?  A mechanical engineer to design a microchip?
If not, then don't expect either one to design software either.
-- 
					David Gudeman
Department of Computer Science
The University of Arizona        gudeman@arizona.edu
Tucson, AZ 85721                 {allegra,cmcl2,ihnp4,noao}!arizona!gudeman