Abstract: 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 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.

Abstract: A display method and apparatus for navigation system enables a user easily see a list of points of interest (POIs) along a route to a destination. The navigation system shows a list of distance ranges of the route where each range shows a number of POIs searched. The current user position is marked in the corresponding distance range. The navigation system displays a list of POI names in the selected distance range where the POI names are arranged in the order that the user sees the POIs along the route. For determining the listing order, the navigation system uses a plurality of region circles having their centers on the route to the destination, and retrieves POIs contained in the region circles and calculates a modified distance of each POI.

Abstract: An input data correction method and apparatus for a navigation system that has a key filtering function to assist the user to determine possible entries for inputting data. The input data correction method includes the steps of displaying a keyboard screen, inputting data through alphanumeric keys on the keyboard screen, positioning a cursor to a location of a character of the input data that is desired to be changed, searching for candidate entries that match the input data if the character at the cursor location of the input data is changed, highlighting alphanumeric keys corresponding to the characters to change the character at the cursor location so that the input data after the change match with the candidate entries, and selecting one or more highlighted keys thereby changing the input data to the candidate entry.

Abstract: A display method and apparatus for a navigation system continuously provides the user the predetermined type of information, typically, the route to the destination even when the user changes the screen to any type of screen in the middle of the route guidance mode. The display method is comprised of the steps of starting a route guidance mode for guiding a user to a destination, detecting whether a user has changed to a new screen different from that in the route guidance mode, determining whether the user has reached the destination, displaying a route guidance screen within the new screen when the user has not reached the destination.

Abstract: A computer-implemented data sorting method for sorting data at high speed with small memory capacity. The sorting method sorts an array of data where sorted data is constituted by a combination of a plurality of blocks where each block is produced separately from one another during the sorting process. In another aspect, a navigation method and system utilizes the data sorting method for quickly sorting and displaying requested information such as POIs sorted by distance with use of a small memory.

Abstract: A display method and apparatus for navigation system enables a user easily see a list of points of interest (POIs) along a route to a destination. The POI names are arranged in the order that the user sees the POIs along the route. The method first determines a route to the destination, and specifies a search area by selecting a distance range on the route from a user position and by defining a radius of a region circle. The method further creates a plurality of region circles consecutively on the route, retrieves points of interest (POIs) within the search area, calculates a modified distance of each POI based on distances from two reference points to the POI and distances from the user position to the two reference points, and lists the POIs in the order of modified distance.

Abstract: A display method and apparatus for navigation system enables a user easily see a list of points of interest (POIs) along a route to a destination. The navigation system shows a list of distance ranges of the route where each range shows a number of POIs searched. The current user position is marked in the corresponding distance range. The navigation system displays a list of POI names in the selected distance range where the POI names are arranged in the order that the user sees the POIs along the route. For determining the listing order, the navigation system uses a plurality of region circles having their centers on the route to the destination, and retrieves POIs contained in the region circles and calculates a modified distance of each POI.

Abstract: A display method and apparatus for navigation system enables a user easily see a list of points of interest (POIs) along a route to a destination. The POI names are arranged in the order that the user sees the POIs along the route. The method first determines a route to the destination, and specifies a search area by selecting a distance range on the route from a user position and by defining a radius of a region circle. The method further creates a plurality of region circles consecutively on the route, retrieves points of interest (POIs) within the search area, calculates a modified distance of each POI based on distances from two reference points to the POI and distances from the user position to the two reference points, and lists the POIs in the order of modified distance.

Abstract: 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.

Abstract: A data sorting method for sorting data at high speed with small memory capacity. The sorting method sorts an array of data where sorted data is constituted by a combination of a plurality of blocks where each block is produced separately from one another during the sorting process. In another aspect, a navigation method and system utilizes the data sorting method for quickly sorting and displaying requested information such as POIs sorted by distance with use of a small memory.

Abstract: A method for finding a shortest overall path length from the start to the final destination when a user of a navigation system wants to visit many intermediate destinations before the final destination. The method includes the steps of calculating a route to all of the destinations and tentatively determining an overall route specifying an order of tour destination where the overall route includes two or more route segments each connecting two destinations, checking the overall route as to whether any two route segments intersect with one another, and identifying the destinations of the route segments intersecting one another and reversing the order of destinations so that the two route segments no longer intersect one another.