On May 4, 1:27 am, Brettster <brett.ba...@[EMAIL PROTECTED]
> wrote:
> My regular walk to the Beverly Hills Public Library seems like a
> gradual uphill climb -- nothing on par with San Francisco, but a very
> slight incline most or all of the way. As you might expect, the walk
> back home is a breeze. According to my handheld Garmin GPS, it's
> exactly 1.75 miles each way. But I wondered exactly how much height I
> was achieving on my walk, in addition to the distance. How can I tell?
> Can a handheld device measure something like that? It could be several
> feet or, I suppose, it could be more. I have utterly no idea. Any
> ideas?
All gps receivers calculate altitude (as the calculated position is a
point in 3D space, not just a horizontal position), but whether they
choose to display it is up to the unit. As previously mentioned,
altitude is notoriously inaccurate - this is because the algorithm is
biased to give preference to satellites that are near the horizon, in
order to improve horizontal accuracy. Mine can be out by over 100 feet
or more.
Some units include a barometric altimeter (and a magnetic compass as
well), but whether this is more accurate or not, I can't say, what
with changing air pressure.
http://www.gpscity.ca/
is a decent place to look up specs.
--
Ray
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