A function to extract and return the computational grid from a gridded analysis.
getGrid(mod, returnclass = "SpatialPolygonsDataFrame")
a SpatialPolygonsDataFrame in which Monte Carlo expectations can be stored and later plotted.
an object of class mcmcspatsurv, returned by the function survspat
the class of object to return, default is a'SpatialPolygonsDataFrame'. Other options are 'raster', which returns a raster brick; or 'SpatialPixelsDataFrame'