The function 'raster' from the 'raster' package provides methods to create a RasterLayer object. RasterLayer objects can be created from scratch, a file, an extent object, an image object, and other specific R objects (i.e. Raster*, Spatial*, im (spatstat); asc, kasc (adehabitat*), grf (geoR) or kde object).
To explore the contents and characteristics of a loaded raster we simply type its name.
EXAMPLES
Examples of how to load raster objects from files are presented below. Examples are provided for the three possible cases:
The examples are taken from the “Effects of Cyclone Yasi on Green Cover at Mission Beach” tutorial. It can be beneficial to put the code snippets in context by looking at a broader section of the R script. Boxes with grey background contain code snippets, and boxes with white background containt code (text) outputs.
We start by creating a path for the location where our raster file is stored
Since our files of interest are located in our current working directory we use the function ‘getwd’ to retrieve the absolute path of our current working directory of the R process. This step is not necessary. We could just (repeatedly) include the path to the data file in the ‘raster’ function call.
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Load a Single Layer Raster from a Single Layer File
Example 1
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Example 2
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Load a Single Layer Raster from a Multiple Layer File
Example 1
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Example 2
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Load a Multiple Layer Raster from a Multiple Layer File
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