vcrop: Virtual grid modification

In hypertidy/vaster: Tools for Raster Grid Logic

Virtual grid modification

Description

To modify a grid is to align an extent to the grid origin. Modification includes to reduce or extend the area covered, in either dimension. This implies a new extent, snapped to the grain of the origin grid and a new size (dimension in x,y).

Usage

vcrop(x, dimension, extent = NULL, ..., snap = "out")

Arguments

x	extent of candidate grid (vector of xmin,xmax,ymin,ymax)
dimension	integer ncol, nrow
extent	numeric extent xmin,xmax,ymin,ymax
...	ignored
snap	one of "out" (default), "near", or "in"

Details

This works for any grid, the input extent can be within the original, an extension of the original, or completely non-intersecting the original grid.

Examples

## any arbitrary extent
x <- c(sort(runif(2, -180, 180)), sort(runif(2, -90, 90)))
print(x)
vcrop(x,  c(360, 180), c(-180, 180, -90, 90))

hypertidy/vaster documentation built on June 10, 2025, 8:09 a.m.