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API reference

Index

Building cubes

GeometryLookup
Geometry
vectordatacube
vectordatacubetable
VectorDataCubes.VectorDataCubeTable
VectorDataCubes.spatialtree

Selectors

A GeometryLookup resolves DimensionalData's selectors spatially: each one narrows the candidates with the spatial tree, then refines them with an exact GeometryOps predicate. VectorDataCubes.mask turns any of them into a Bool mask.

On the Geometry axis:

  • Contains(point): every geometry covering the point; closed, so a point on a shared border belongs to each geometry it lies on.
  • At(geom): the geometry equal to geom; Near(point): the nearest geometry, ties to the lowest index.
  • Touches(extent): the geometries intersecting the extent.
  • Where(f): the geometries f holds for; a curried GeometryOps predicate such as GO.intersects(geom) is narrowed by the tree first.
  • A DE9IM.jl predicate, DE9IM.Covers(geom) and the like.

On the internal X/Y axes, pairs: At/At, Contains/Contains, Near/Near, two intervals (geometries covered by the box) and Touches/Touches (geometries intersecting it), as cube[X(At(x)), Y(At(y))] or cube[X(a .. b), Y(c .. d)].

VectorDataCubes.mask

Coordinate reference systems

A lookup carries its crs (GeoInterface.crs, set with Rasters.setcrs), and Rasters.reproject reprojects it through GeometryOps.reproject, which needs Proj.jl loaded. Reprojecting a lookup with no crs is an ArgumentError; set one first.

Zonal statistics

zonal is deliberately not exported (Rasters exports a zonal too); call it qualified as VectorDataCubes.zonal, or bind it with using VectorDataCubes: zonal.

VectorDataCubes.zonal

Point extraction

extract is likewise not exported (Rasters exports an extract too); call it qualified as VectorDataCubes.extract, or bind it with using VectorDataCubes: extract.

VectorDataCubes.extract

Plotting

With Makie loaded, a GeometryLookup — and any dimension wrapping one, such as the Geometry dimension of a cube — is a plottable object: poly, lines and scatter convert its geometries to GeometryBasics and hand them to Makie's own recipes, and plot picks the recipe from the kind of the first geometry:

  • polygons, multipolygons and linear rings to poly,
  • linestrings and multilinestrings to lines,
  • points and multipoints to scatter.

Pass one value per geometry as color for a choropleth:

using Makie
poly(dims(cube, Geometry); color = cube[Ti = 1])

A lookup mixing single and multi geometries of one family (polygon/multipolygon, linestring/multilinestring, point/multipoint) is lifted to the multi kind before plotting. Any other mixture, and an empty lookup, is an ArgumentError.

A cube passed to plot goes to DimensionalData's own Makie extension, which has no notion of a geometry axis and fails to convert it. Plot the Geometry dimension and pass the cube's values as color, as above.