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First of all, I hope this question isn't too basic, obvious or inappropriate for this forum. I'm very new to using map data. I'm working on a project on locating service terminals in a geographic region. Abstractly, given a simply connected region in the plane (for the purposes of what I'm doing, a contiguous map, say a map of the contiguous United States), I want to approximately cover this map with non-overlapping circles that lie completely in the boundary. (This is only part of what I'm doing, but it's the relevant part). I'm working on programming an algorithm for this in MATLAB.

My question related to this is:

I have map data in I've downloaded from TIGER ( I've successfully opened this map data in MATLAB using the Mapping toolbox Map Viewer. What I want to do is to take this nice looking map data and store it in format I can use.

A crucial part of the algorithm I'm implementing has a step that is:

Given a point (x,y), calculate the distance from this point to the boundary of the region. For my purposes, this is Euclidean distance, i.e., the length of the shortest straight line from (x,y) to the boundary.

What would be a way to go from the TIGER data (which gives me a nice picture of the map) to a format that I can easily calculate the above step?

Thank you!

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Matlab has a function to read in shapefiles. Census data is in a geographic projection which is not terribly useful for distance calculations. You may want to use OGR to project it to a suitable coordinate system, first.

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