On Wed, 1 Oct 1997 [log in to unmask] wrote:
> POSTAL CODES: this is easily handled in Coverage as a
> scheme - e.g., "U.S.ZipCode". Andrew Daviel has reasons
> why postal codes ain't perfect.
Post codes are for sorting post for hand delivery, and may do
interesting things like put opposite sides of the same street in different
codes. The Canadian ones are radically different sizes in different parts
of the country (by at least 3 orders of magnitude). However, as part
of an address element, they're certainly valuable.
>
> GLOBAL POSITIONING SYSTEMS: GPS are highly precise systems,
> and again I see this as Just Another Scheme. And here again,
> I turn this over to Andrew (he and I had an email exchange
> on this about ?a year? ago)
After much discussion, both with myself and with others,
coverage.x,y,z is basically GPS co-ordinates (WGS84 datum) in degrees
and metres. Various software exists to convert from other datums (NAD27,
etc.)
As suggested in another mailing, though no-one is going to type in
lat/long as a search term, they might well enter "within 10 km of Boston"
or click a map.
Andrew Daviel
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