The most fundamental idea I'd like to convey is that you should design your code, not just write a huge .pro file.

To help avoid wasted time and headaches later, there are a few very basic things that can be done when you first start an IDL programming project:

• Put a header on ALL your programs. I just cut and paste the following into the very beginning of all my programs and edit it as appropriate:

;---------------------------------------------------------------------
;    Plots DN as a function of pitch angle in degrees for EPD data.
;    - B. Bhattacharya, 02/02/98
;
;    Modification History:
;        Changed to plot out both high lats and mag eq daa on same 
;             plot,BB, 2/4/98
;        Removed the above and replaced with multi-panel plots of 
;             all records, BB, 3/12/98
-------------------------------------------------------------------

• Instead of writing huge programs that perform several or all of the functions that you need, develop separate modules that execute one part of the job. This will make it MUCH easier to add in new variables or remove old ones, debug your code, and add on new functionality. Here's what I mean:
  

main_driver.pro - calls all the other programs

read_file.pro - declares arrays, opens files, reads data in, closes file

mega_calc.pro - calculates the answer to the question of the meaning of life

plot.pro - displays your results in a nifty way

As a rule, I try to keep individual programs to less than 100 lines each and I write a new module each time I want to do something new. It's easy to let all your routines have access to the neccessary variables by declaring them as part of a COMMON BLOCK.


• Create a README file in each directory so that months from now you will remember what you were doing like this:

The s/w in this directory reads in pitch angle and dn data 
files and plots at high lat or at the mag equator. The file 
plotpa.single.pro singles out either the high lats or mag eq data, 
and the file plotpa.pro does both.

-B. Bhattacharya

04 February 98

Bidushi Bhattacharya
Dept of Atmos Sciences
UCLA
16 April 1998
bhattach@atmos.ucla.edu