XPost: rec.arts.sf.written, rec.arts.sf.science   
   From: gossg@gossg.org   
      
   Dimensional Traveler  wrote:   
      
   >There are all kinds of problems with GPS based directions systems and   
   >software.  IME almost always because the map is wrong.  I've run into I   
   >don't know how many cases of the directions suddenly becoming   
   >effectively gibberish because the actual road was 50 feet off to one   
   >side of where the map thinks it is and thinks you are either driving   
   >thru buildings or cross country across the desert.   
      
   There is a large chunk of rural southern Alberta where both of our   
   GPSs thought we were about a half mile east of where we really were.   
   One of them "adjusted" us to the nearest rural road, while the other   
   just had us driving through the canola.   
      
   I assume that both GPSs bought the map from some supplier with   
   defective placement of that rather large chunk of my province.  And   
   that prior to GPSs, the supplier never noticed the misalignment of a   
   big chunk of map.   
      
   Between Alberta and BC are several mountain ranges.  Driving in narrow   
   canyons, you have a view of a limited number of satellites, and the   
   signal from those few can bounce off cliffs and give false readings.   
   I fairly often get directions from some minor trail across the river   
   to try to get me back onto the highway I'm still on.   
      
   >The worst instance   
   >I've experienced the difference between map and reality was about two   
   >miles (one of the SW desert states).   
      
   --   
   We are geeks.  Resistance is voltage over current.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)