Package index

The grid

A grid is a list of four things: dimension, extent, crs, values. These make one, ask it questions, and hand it to another package.

grid_spec()

A grid, as a plain list

grid_xy()

Coordinates of the cell centres

grid_ncell()

Number of cells in a grid

grid_res()

Cell size in each direction

is_grid()

Is this a guerrilla grid?

as_grid()

Read another package's raster as a grid

as_raster() as_terra() as_gdalraster()

Hand a grid to another package

plot(<guerrilla_grid>)

Plot a grid

as.matrix(<guerrilla_grid>)

Turn a grid into a matrix

as.data.frame(<guerrilla_grid>)

Turn a grid into a data frame

Interpolation

Every one of these takes coordinates, values and a grid, and returns a grid. They differ in what they assume, and the documentation says what.

grid_bin()

Bin values into grid cells

grid_voronoi()

Nearest neighbour interpolation, by Voronoi tessellation

grid_barycentric()

Interpolate to a grid across a triangulation

grid_idw()

Inverse distance weighted interpolation

grid_tps()

Thin plate spline interpolation

grid_kriging()

Kriging

grid_gam()

Generalized additive model on the coordinates

grid_smooth()

Kernel smoothing on a grid

grid_gdal()

Interpolate with GDAL's own gridder

mesh_raster()

Mesh raster

The arithmetic, in the open

The parts other packages keep in C. These exist to be read, and to check that the fast paths compute what they claim to.

bary_weights()

Barycentric coordinates of points within a triangle

find_triangle()

Which triangle is each point in?

grid_facet_lm()

Fit a plane within each Delaunay triangle

Input

xyz_input()

Coordinates and values, from whatever you have

collapse_duplicates()

Collapse coordinates that repeat

Data

bathy

Bathymetry and topography for the BROKE-West region

The package

guerrilla guerrilla-package

guerrilla: Illustrate Various Methods of Interpolation for Irregular Data

Superseded

Kept so old code runs. Each one’s help page says what to use instead and why.

tri_fun()

Interpolation to a regular grid via triangulation

defaultgrid()

Create a target grid for interpolation

facets()

Interpolate by fitting a plane within each tessellation facet