In adamlilith/fasterRaster: Faster Raster and Spatial Vector Processing Using 'GRASS GIS'

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fasterRaster has limited support for 3-dimensional GRasters and GVectors. A GRaster is like a multi-layered raster, except that layers contain values in "voxels" (3-dimensional pixels), where each layer has a z-resolution, in addition to its normal x- and y-resolutions. These layers are called "depths". A 3-dimensional vector has a z-dimension, so any point (i.e., an actual point, or points that together define a line or polygon) has a third dimension. You can test if an object is 3-dimensional using topology(), is.2d(), or is.3d(), or by looking at its metadata (i.e., just enter the name of the object in R and look at what is displayed).

Thus far, no functions that handle 3-dimensional GRasters or GVectors have been tested. Some functions like spatSample() have arguments that allow you to do something with a z-component. Also, some of the "getter" functions can report information about the third dimension of a GRaster or GVector.

Three-dimensional GRasters and GVectors should (?... remember, no testing yet!) work with most functions. In some cases, the third dimension will be ignored or removed. You should get a warning in these cases.

fasterRaster functions that specifically work with 3-dimensional objects

| Function | Object type | | --------------------------|------------------------- | | bottom() | GRaster or GVector | | dim3d() | GRaster | | is.2d() | GRaster or GVector | | is.3d() | GRaster or GVector | | ncell3d() | GRaster | | ndepth() | GRaster | | res3d() | GRaster | | top() | GRaster or GVector | | topology() | GRaster or GVector | | zext() | GRaster or GVector | | zres() | GRaster |

~ FINIS ~

adamlilith/fasterRaster documentation built on Dec. 21, 2024, 2:04 a.m.