![]() ![]() If a NoData value is not specified, the system will find an empty value to use as the NoData placeholder, which may not be desired or expected. Specifying the NoData value allows you to control the pixel depth and the value that will store NoData. When a graphic is used to clip your data, NoData pixels will most likely exist in the output. When exporting your data to a file-based raster dataset using a clipping option, it is recommended that you enter a NoData value. ![]() Optionally, you can use the Copy Raster tool to capture raster dataset parameters settings in the geoprocessing tool history. If you want to retain a record of your parameter settings using the Export Raster pane, you need to record them manually. Contributions were also made by Jochen Albrecht, Neil Best, Andrew Bevan, Roger Bivand, Isabelle Boulangeat, Lyndon Estes, Josh Gray, Tim Haering, Herry Herry, Paul Hiemstra, Ned Hornig, Mayeul Kauffmann, Bart Kranstauber, Rainer Krug, Alice Laborte, John Lewis, Lennon Li, Justin McGrath, Babak Naimi, Carsten Neumann, Joshua Perlman, Richard Plant, Edzer Pebesma, Etienne Racine, David Ramsey, Shaun Walbridge, Julian Zeidler and many others.Note:Parameter settings in the Export Raster pane are not recorded in the geoprocessing tool history. Significant help was also provided by Phil Heilman, Agustin Lobo, Oscar Perpinan Lamigueiro, Stefan Schlaffer, Jon Olav Skoien, Steven Mosher, and Kevin Ummel. Spatial queries between Spatial* and Raster* objectsĬoerce coordinates of SpatialLines or SpatialPolygons into a ameĮxtensive contributions were made by Jacob van Etten, Jonathan Greenberg, Matteo Mattiuzzi, and Michael Sumner. Select - interactively select spatial features Symmetrical difference of two SpatialPolygons* objectsĭissolve smaller polygons into larger onesĮxplode: turn polygon parts into separate polygons (in the sp package)Ĭlip a Spatial* object using a rectangle (Extent object) Update and identity for a SpatialPolygons and another one bindĪppend combine Spatial* objects of the same (vector) type The name in bold is the equivalent command in ArcGIS. Some of these functions are in the sp package. Manipulation of SpatialPolygons* and other vector type Spatial* objects Row numbers from y-coordinates (or latitude) Likewise, row numbers start at 1 at the top of the raster, and column numbers start at 1 at the left side of the raster.Ĭolumn numbers from x-coordinates (or longitude) ![]() They increase within rows, from left to right, and then row by row from top to bottom. Computing row, column, cell numbers and coordinatesĬell numbers start at 1 in the upper-left corner. Get or set the NA value (for reading from a file) How many bands (layers) does the file associated with a RasterLayer object have? Layer (=band) of a multi-band file that this RasterLayer is linked to Test if an object has a longitude/latitude coordinate reference systemįilename to which a RasterLayer or RasterBrick is linked The coordinate reference system (map projection) The extent (minimum and maximum x and y coordinates) The number of cells (can not be set directly, only via ncol or nrow) Similarly, with projection you can set the projection, but this does not transform the data (see projectRaster for that). This is not the case when the extent is changed (as the number of columns and rows will not be affected). If there are values associated with a RasterLayer object (either in memory or via a link to a file) these are lost when you change the number of columns or rows or the resolution. Getting and setting Raster* dimensionsīasic parameters of existing Raster* objects can be obtained, and in most cases changed. Pairs plot for layers in a RasterStack or RasterBrickīox plot of the values of one or multiple layers X-y scatter plot of the values of two RasterLayer objects Select a geometric subset of a Raster* or Spatial* objectĬreate a SpatialPolygons object by drawing itĬreate a SpatialLines object by drawing it Query values of Raster* or Spatial* objects by clicking on a map Plot the values of a RasterLayer on top of a map Plot a Raster* with the spplot function (sp package) The main method to create a mapĬombine three layers (red, green, blue channels) into a single 'real color' image See the rasterVis package for additional plotting methods for Raster* objects using methods from 'lattice' and other packages. ![]()
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