Hi. This is my first post to the list so apologies if it is not formatted correctly. I have a dataset from a forest survey with trees marked in an arbitrary co-ordinate system of the form: X from 1000 to 1100, and Y from 1000 to 1100. I have recently resurveyed the forest and found trees that I need to add. For the new trees I have recorded angle and distance to existing trees (3 per new tree). So my question is two-fold: 1. Is there a package that anyone can recommend to help me translate these bearings and distances into the existing cartesian co-ordinate system? 2. Is there a way that I can quantify the locational error, assuming that there is a triangular intersect? Any suggestions would be greatly appreciated. Thanks Austin [[alternative HTML version deleted]]