| 摘要 |
A navigation method and system for extracting point of interest (POI) data from a map data source and sorting the POIs by distance from a current user position to display the same at high speed without requiring a large memory. The navigation system aligns the cells each having specified POI in an cell array and classifies the cells into a plurality of different levels based on[, for example, a] distance (first sorting operation) from the current user position, or positions of the cells in the cell array relative to the cell closest to the user position. The navigation system extracts the POIs from the cells in the specified level, sorts the POIs by distance (second sorting operation), and displays the POIs. During each process, the navigation system retrieves and processes only a small amount of POIs sufficient for the current display screen and immediate scrolls of few pages.
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