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- 2007 July
- advice needed: efficient approach to find streets that are close to a given point

Subject: | advice needed: efficient approach to find streets that are close to a given point |

Posted by: | busnet (goog…@00l.de) |

Date: | Thu, 12 Jul 2007 |

Hi.

I've got the following problem: I have a huge xml-file that represents

a street map of a city. Each street is stored as a couple of

coordinates (start, end and all the turns).

I process that file and try to find those streets that are close to a

given point. So what I do is calculate the distances to EACH street

segment (using linear algebra algorithms, that is, constructing the

vector from two points and computing the distance from the given point

to this vector).

Do you have any ideas how to speed up the process of finding the

nearest street(s)?

I tried to consider only those streets whose endpoints are within a

certain range from the given marker-point, but it was not considerably

faster and if there was a street thats very long and straight the

endpoints may be far away, but the street itself could be quite near.

Any help is appreciated!

- Re: advice needed: efficient approach to find streets that are close to a given point posted by Uffe Kousgaard on Thu, 12 Jul 2007