distances between coordinates

hi guys,

I have a problem. I have a set of coordinates in latitude and longitude system, like about 95 coordinates and i arranges it in matrix 95x2. so i would like to find the distances between each coordinates and makes the distances in matrix 95x95. can anybody help me?

[Walter Roberson]

Which distance measure?

For example do you want to simplify as if it was a sphere and you want to find the great circle distances? Or do you want the WGS-84 model? Do you want to include altitude in your calculations?

Answer 1

[Chad Greene]

First, convert lat/lons into some projected x/y using an appropriate projection. After projecting lat/lon to x/y, coordinates will be in units of meters or feet and you can use John D'Errico's ipdm function to get the inter-point distance matrix.