"Peter Clark" wrote in message
...
On Fri, 22 Apr 2005 19:55:22 GMT, Nathan Young
wrote:

It is not as trivial as it should be. METAR decoder software is
difficult to write because of the special weather statements that can
be included in a METAR entry (things like RVR, multiple precip types,
etc).

Simple parsers can grab winds, date, time, and cloud conditions. But
to be all-encompassing requires a bit more. I found a package (via
NOAA?) that would do METAR decodes, and it included approximately 30KB
of source code, which seemed like a lot for the extra bit of
functionality it provided.

30K just for the parser, or did that include station name lookup
tables?


Like most computer code, 20 percent of it probably does the real work....
and the 80 percent is there to make sure that it exits elegantly and does
not run into an infinite loop, crash-to-operating-system, or report
ridiculous value... whenever it is fed garbage input or exceptional
conditions.