extract_array: extract_array

In hmcdevitt/spExtract: Extract values at spatial locations from Raster* objects as matrices

Description

This function extracts the values from an array for a set of spatial coordinates. The coordinates must be in the same projection as the raster layers used to create the array.

Note: currently this function works on only one layer at a time. To extract the value from different layers at the same coordinates this function will need to be used in a loop, changing *third_dim_ind* for each iteration to move through the array temporally. This functionality will be updated in future versions.

Usage

extract_array(array, extent, coords, third_dim_ind, resolution)

Arguments

array	an array with dimensions 1 and 2 being the y and x values (respectively) of the rasters layers, the 3rd dimension is the multiple layers for same spatial extent (i.e. multiple layers of the same area through time)
extent	an extent object. contains xmin, xmax, ymin, ymax of the raster layers used to make the array
coords	a 2 column matrix/dataframe with the x and y coordinates in same projection as extent
third_dim_ind	index of which layer to be used, i.e. third dimension
resolution	a vector with 2 values indicating the x and y resolution of each raster cell

hmcdevitt/spExtract documentation built on July 13, 2020, 2:11 p.m.