Line Zero Problem

Stephmon@aol.com
Mon, 21 Jun 1999 01:39:37 EDT

Hello all,
In light of the recent discussion concerning adding information to line zero, 
I decided to double-check compatibility issues with Satellite Hunting. 
Unfortunately, version 1.0.1 and earlier will produce an error, if an object 
has a line zero longer than 37 columns AND doesn't appear in the SatDesc.dat 
file. I have fixed this in the revision I am currently working on, but 
unfortunately, this is an ambitious revision and I won't be able to release 
it, for at least a week or two. 

For those interested, I was testing for 4 types of line zero.
1) Absent: Read 2 lines per pass. Cross-check SatDesc. If found, use name and 
mean magnitude from file. If not found use COSPAR in place of name and 
default mean mag.
2) Blank: Same as [1], but read 3 lines per pass.
3) Name only (Length >0, and <>37) Cross-check SatDesc for mean magnitude, 
use default if not found.
4) Name and mean magnitude (Length = 37). Cross-check SatDesc for "v" after 
mean mag. If appropriate, substitute "v" value from file, for "d" value in 
TLE.

Unfortunately, a zero line longer than 37 characters was invoking the third 
scenario and causing a fault. When subtracting the length of the existing 
line from 37, a negative number resulted. Since the editing function involved 
doesn't allow negatives, a fault occurs. As many of you are probably thinking 
right now, >= 37 is my new test, and I clip the line at 15 characters (before 
adding the appropriate number of spaces, followed by mean magnitude), if it 
doesn't pass. If anyone would care to offer a more elegant test of the four 
(or perhaps more?) types of zero line, I would be happy to exchange ideas.

I apologize for any inconvenience this may cause. I will be hard at work 
getting this release ready for download as soon as possible (without 
introducing a lot of bugs).

I'd like to take this opportunity to thank those who've contacted me with 
ideas for improvement (I am tackling the majority of them with this next 
release) and especially those who've decided to register. All of your support 
means a great deal, I can't thank you all enough!
______________________
Regards,
Stephen
http://stephen.fathom.org/