The '______ already defined' error (r(110)) is usually not a problem  
for me; I just start with a new variable to define or drop the  
existing one.  BUT how can I find what the problem is when I'm looping  
through unique values of a variable?
I'm still working on some spatial analysis and when I create my  
haversine variable (with the option of that name in the -vincenty-  
command) in the forvalues loop I get the error message just  
referenced...and I'm not doing anything esle in the code that is  
demanding a change on this new distance variable.
Thanks for your help,
Diego
--------------------------------------------
David Diego Torres, MA(Sociology)
PhD Candidate in Sociology
2030D Population Studies Center
University of Michigan Institute for Social Research
Ann Arbor MI  48106-1248
Tel 734.763.4098
Fax 734.763.1428
torresd at umich dot edu
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