Calculate the number of tracks through a voxel

Source: R/voxel_around_centre.R

A voxel is the 3D equivalent of a pixel. Counts the number of unique tracks going through a voxel. The function rotates the tracks according to the average wind direction of the track. The x direction is parallel to the wind direction.

voxel_around_centre(
  local,
  centre,
  max_distance = 200,
  voxel_size = rep(max_distance/5, 3),
  voxel_box = matrix(c(-10, -10, 0, 10, 10, 20), nrow = 3)
)

Arguments

local

the connection to the local database

centre

a data frame with a single row and x and y coordinates of the centre. Coordinates in CRS 31370

max_distance

Use all equal time tracks where the minimum distance in meters between the track and the centre is smaller than max_distance.

voxel_size

Size in meters of the voxel.

voxel_box

Defines the area around the centre for to set of voxels to use. Defined using the index number of the voxels. Defaults to 10 voxels on both side of the centre in x and y and 20 voxels above 0 in the z direction.