Select n
landmarks that are spaced with a regular sequence of angles taken
between the outline coordinates and the centroid.
Arguments
- x
A
matrix
, adata.frame
alist
of perimeter coordinates, often produced withobject_contour()
.- n
Number of points to be sampled. Defaults to 50.
- close
Return a closed polygon? Defaults to
TRUE
.- plot
Create a plot? Defaults to
TRUE
.- ncol, nrow
The number of rows or columns in the plot grid when a
list
is used inx
. Defaults toNULL
, i.e., a square grid is produced.
Value
A list with the following objects:
pixindices
: Vector of radius indices.radii
: Vector of sampled radii lengths.Xc
: The centroid coordinate ofx
axis.Yc
: The centroid coordinate ofy
axis.coords
: Coordinates of sampled points arranged in a two-column matrix.
If x
is a list, a list of objects described above is returned.
Examples
library(pliman)
plot_polygon(contours[[1]])
ldm <- landmarks_regradi(contours)