Patent ID: 8626438
Filing Date: 2014-01-07
Classification: G01C,G09B

Abstract:
1. A method of encoding a continuous path within a road network, said path being completely represented within a digital map and expressible as a path list of at least one of lines and segments existing in said digital map and consecutively ordered, said method comprising: (i) storing a start position in a route search list, said start position being one of: the line or segment first appearing in said path list or, where the start node of said first line or segment in said path list is artificial, the first line or segment appearing in said digital map having a real start node and which leads directly to said first line or segment optionally through other artificial nodes, a most recently identified deviation line or segment also appearing in said path list, (ii) determining a path from the start node of the start position and including said start position to an end node of the last line or segment in the path list within said digital map, said path being determined according to an algorithm, (iii) comparing the shortest path so determined to the path list for identity, and in the absence of identity, identifying at least one deviation line or segment being part of the path list and having a start node representative of an intersection in said digital map but not being the line or segment first appearing in said path list, and if such deviation line or segment does not terminate at the end node of the last line or segment appearing in the path list, repeating step (i) using said deviation line or segment, and (iv) storing the last line or segment in the path list in said route search list if not already stored.