LBS290                       DEBUGGING PROGRAMS

There are a number of techniques wihch you can use to find errors in your
program when it executes.  The best technique is to write clean well
structured programs using good style and clear variable names.

However the best programs can have small errors which are hard to find.
An excellent techinque to find these errors is to add extra print statements
to your program in the area which seems to have the problem.  This
technique is called "debugging printouts".  Hopefully you will be able
to narrow the possible locations of the problem to a single statement
quite quickly.

Another excellent technique for quickly developing programs is to start 
with a simple subset of the program and get it working with debugging 
printouts as necessary.  Test the simple subset of the program and once
the initial part is working begin to add details slowly.  Carefully
test each added feature and then you should be able to evolve your
program to satisfy the complete set of requirements for the problem.

It is much easier to get a 30 line program to work than a 200 line 
program. Once the 30 line program works - it is quite easy to add 10
lines and keep the program working.