Marco,

When we look at a GPS error value in a so-equipped GPS, does that value
reflect *both* the vertical (i.e. altitude) and the horizontal
component? Can a separate value for each be determined?


The error values commonly given a

VDOP: Vertical Dilution of Position
HDOP: Horizontal Dilution of Position
PDOP: 3-D dilution of position, i.e. the above two combined

Most GPS receivers show these values.

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--
Thomas Borchert (EDDH)