[R] R implementations of scatterplot/map labeling algorithims?

[Michael Friendly]

Dear R community

In a current paper, I'm (briefly) considering the topic of producing
scatterplots or maps with point labels positioned in such a way as to 
minimize label overlap and occlusion.  This is a topic with a large, but 
scattered literature. In CS, it is considered NP-hard, but there are
a variety of approximate solutions.  The most complete bibliography I've 
found is
the Map-Labeling Bibliography,
http://liinwww.ira.uka.de/bibliography/Theory/map.labeling.html

AFAIK, the only concrete and published implementation is a Fortran
program published by Noma (below), and then adapted by Warren Kuhfeld
at SAS in PROC PLOT, and used in his %plotit macro.

     Journal Title  - Psychometrika
     Article Title  - Heuristic method for label placement in scatterplots
     Volume  - Volume 52
     Issue  - 3
     First Page  - 463
     Last Page  - 468
     Issue Cover Date  - 1987-09-27
     Author  - Elliot Noma
     DOI  - 10.1007/BF02294366
     Link  - http://www.springerlink.com/content/c4k6205r83156165

Does anyone know of a related R (or other) public implementation of a 
solution to this problem?

thanks,
-Michael

-- 
Michael Friendly     Email: friendly AT yorku DOT ca
Professor, Psychology Dept.
York University      Voice: 416 736-5115 x66249 Fax: 416 736-5814
4700 Keele Street    http://www.math.yorku.ca/SCS/friendly.html
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