Dear all, I am happy to announce that a new version of the *spsann* package is now on CRAN.
The *spsann* package has methods to optimize sample configurations using spatial simulated annealing. Multiple objective functions are implemented for various purposes, such as variogram estimation, spatial trend estimation and spatial interpolation. A general purpose spatial simulated annealing function enables the user to define his/her own objective function. A solution for solving multi-objective optimization problems are available as well. Now you can use *spsann* to augment an existing sample configuration, that is, add new sampling points to a spatial sample configuration generated using *spsann* or any other means. To do so, when using one of the functions from the family of optim...() functions, you must pass to the function argument points an object of class list containing two named sub-arguments: fixed, a matrix or data frame with the coordinates of the existing sample configuration -- kept fixed during the optimization --, and free, the number of sample points that should be added to the existing sample configuration -- free to move around during the optimization. The latest application of the *spsann* package was for the optimization of the locations of rain-gauges to increase the accuracy of predictions of rainfall fields in an area north-east of the city of Manchester, United Kingdom. More information is available in the paper published by Alexandre Wadoux <http://www.wur.nl/en/Persons/Alexandre-AMJC-Alexandre-Wadoux-MSc.htm> and collaborators which you can download from https://doi.org/10.1016/j.advwatres.2017.06.005. With best regards, -- Alessandro Samuel-Rosa /Estagiário Pós-doutoral (2016-17) Universidade Federal de Santa Maria Visite meu website <http://samuel-rosa.github.io>! / ------------------------------------------------------------------------ *Fe-BR: Base de Dados Brasileira de Ferro do Solo * Uma base de dados de ferro do solo centralizada, pública e gratuita, com cobertura nacional. Visite www.ufsm.br/febr <http://coral.ufsm.br/febr/contribute.html> e veja como contribuir. [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-geo
