The gstat Package - NexTag Supports Open Source Initiatives

38 predict.gstatValueMemory requirements for sequential simulation: let n be the product of the number of variables,the number of simulation locations, and the number of simulations required in a single call. thegstat C function gstat_predict requires a table of size n * 12 bytes to pass the simulationsback to R, before it can free n * 4 bytes. Hopefully, R does not have to duplicate the remaining n *8 bytes when the coordinates are added as columns, and when the resulting matrix is coerced to adata.frame.Useful values for debug.level: 0: suppres any output except warning and error messages; 1:normal output (default): short data report, program action and mode, program progress in %, totalexecution time; 2: print the value of all global variables, all files read and written, and includesource file name and line number in error messages; 4: print OLS and WLS fit diagnostics; 8: printall data after reading them; 16: print the neighbourhood selection for each prediction location; 32:print (generalised) covariance matrices, design matrices, solutions, kriging weights, etc.; 64: printvariogram fit diagnostics (number of iterations and variogram model in each iteration step) andorder relation violations (indicator kriging values before and after order relation correction); 512:print block (or area) discretization data for each prediction location. To combine settings, sum theirrespective values. Negative values for debug.level are equal to positive, but cause the progresscounter to work.For data with longitude/latitude coordinates (checked by is.projected), gstat uses great circledistances in km to compute spatial distances. The user should make sure that the semivariogrammodel used is positive definite on a sphere.a data frame containing the coordinates of newdata, and columns of prediction and predictionvariance (in case of kriging) or the columns of the conditional Gaussian or indicator simulationsAuthor(s)Edzer J. PebesmaReferencesN.A.C. Cressie, 1993, Statistics for Spatial Data, Wiley.http://www.gstat.org/Pebesma, E.J., 2004. Multivariable geostatistics in S: the gstat package. Computers & Geosciences,30: 683-691.For bucket PR quadtrees, excellent demos are found at http://www.cs.umd.edu/~brabec/quadtree/index.htmlSee Alsogstat, krigeExamples# generate 5 conditional simulationsdata(meuse)coordinates(meuse) = ~x+y