[aprssig] APRS LAT/LONG standards

Tapio Sokura oh2kku at iki.fi
Sun May 29 21:35:19 EDT 2005


Steve Dimse wrote:
> Much as I hate to admit it, I'm on Bob's side on this one, I share  his 
> frustration at people not reasoning problems through. The only  piece of 
> info one needs to answer your original question is that  there are 60 
> seconds in a minute, hardly an arcane bit of trivia.  After that, it is 

Yeah, looks like I forgot to say the most important thing along with the 
example. Knowing that there are 60 minutes in a degree and 60 seconds in 
a minute should be sufficient for figuring out how it goes in practice. 
There's no need to memorize exact formulas, just understand the 
principle and the "formula" will follow that.

An example on the calculations is useful in many cases though, 
especially on more complex things like converting coordinates from one 
system of coordinates to another. Numerous are the occasions I have 
banged my head onto a wall when the only mistake in a formula is one 
misplaced digit or a multiplication turned into a division. It's easier 
to catch these when you have a reference calculation with all middle 
values to compare to. (I'm not a geodetic by profession so I guess I can 
confess here that I really don't understand all the math involved in the 
complicated transformations, but I can duplicate formulas and examples..)

> grade school math...been a while, but I think it  was 4th or 5th grade 
> when one learns about converting fractions to  decimal.

But you still seem to cling onto your fractions in the stock market etc 
:-)  Ok, enough intercontinental joking..

   Tapio




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