Hello list I have been trying to figure out if it is possible to select a subset of data in a SpatialGridDataFrame without prior conversion to a data.frame using the method as.data.frame().
I have imported an ESRI " *. bil " file containing different spectral bands using rgdal. The file imported as a SpatialGridDataFrame. The data originates from an aerial photograph of a row crop and I would like to select pixels from within a row as opposed to those from the inter-row space for further interpolation. Inter-row pixels have a different signature and therefore may be potentially screened out. However, I have been unable to access the SpatialGridDataFrame directly with, for example, a subset(x, band5 < lowerLimit, select c(a, b) ) call for selecting values according to given criteria. Am I using the wrong strategy, should I just demote the spatial class using method as.data.frame(), do the manipulation and then promote the screened values back to a spatial class? Regards Karl _________________________________ Karl J Sommer, Department of Primary Industries, PO Box 905 Mildura, VIC, Australia 3502 Tel: +61 (0)3 5051 4390 Fax +61 (0)3 5051 4534 Email: [EMAIL PROTECTED] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo
