Hello list I am making reference to the graph gallery at http://r-spatial.sourceforge.net/gallery I was wondering how one would go about adding elevation contour lines to the example fig08? Presuming that one would have access to a number of geo-referenced elevation measurements with a similar density as the sampling locations indicated with a grey x in fig08. Is there a method to generate contour lines from such information and overlay it onto the existing interpolated graph? Cheers Karl Sommer _________________________________ Karl J Sommer, Department of Primary Industries, Catchment & Agriculture Services, PO Box 905 Mildura, VIC, Australia 3502 Tel: +61 (0)3 5051 4390 Fax +61 (0)3 5051 4534 Email: karl.sommer at dpi.vic.gov.au
generate & plot elevation contour lines
2 messages · karl.sommer at dpi.vic.gov.au, Edzer Pebesma
karl.sommer at dpi.vic.gov.au wrote:
Hello list I am making reference to the graph gallery at http://r-spatial.sourceforge.net/gallery I was wondering how one would go about adding elevation contour lines to the example fig08? Presuming that one would have access to a number of geo-referenced elevation measurements with a similar density as the sampling locations indicated with a grey x in fig08. Is there a method to generate contour lines from such information and overlay it onto the existing interpolated graph? Cheers Karl Sommer
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Simpler than I thought it would be: add contour = TRUE to the argument list of spplot. If you want the actual contours, there is a contourLines function that returns them; sp has a function to convert these to SpatialLinesDataFrame objects: contourLines2SLDF(). -- Edzer