gis - Regd. map grid structure in GPS data mining -


i have been exploring gps data mining literature esp. problems anomalous trajectory detection, time travel prediction, etc , 1 common method see dividing data or map grids. can 1 please explain logic of this? coordinates euclidean in case? grid decomposition necessary? grateful if can give/ quote links or materials should explore. new field, please pardon me if question obvious.

thanks & regards, lesnar

no not euclidean. don't have be. grids not rectangles anymore, can treated such operations.

if create lat/long grid, each cell means of meters not rectangular. defines zone add counter, has clear inside/outside definition. , can use cartesian operations (rectangle.inside())

so lat / lon span constant each cell, not longitudinal meters span, shrinks cos(latitude).

if 1 needs grid equal grid cells sizes means of meters, 1 has transform geo coordinates before.


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