lidR: segment_shapes – R documentation

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segment_shapes

Estimation of the shape of the points neighborhood

Description

Computes the eigenvalues of the covariance matrix of the neighbouring points using several possible algorithms. The points that meet a given criterion based on the eigenvalue are labeled as approximately coplanar/colinear or any other shape supported.

Usage

segment_shapes(las, algorithm, attribute = "Shape", filter = NULL)

Arguments

`las`	an object of class LAS
`algorithm`	An algorithm for shape detection. lidR has: shp_plane, shp_hplane and shp_line.
`attribute`	character. The name of the new column to add into the LAS object.
`filter`	formula of logical predicates. Enables the function to run only on points of interest in an optimized way. See also examples.

Value

A LAS object with a new column named after the argument attribute that indicates those points that are part of a neighborhood that is approximately of the shape searched (TRUE) or not (FALSE).

Examples

## Not run: 
LASfile <- system.file("extdata", "Megaplot.laz", package="lidR")
las <- readLAS(LASfile)

las <- segment_shapes(las, shp_plane(k = 15), "Coplanar")
#plot(las, color = "Coplanar")

# Drop ground point at runtime
las <- segment_shapes(las, shp_plane(k = 15), "Coplanar", filter = ~Classification != 2L)
#plot(las, color = "Coplanar")

## End(Not run)

lidR

Airborne LiDAR Data Manipulation and Visualization for Forestry Applications

v3.1.2

GPL-3

Authors

Jean-Romain Roussel [aut, cre, cph], David Auty [aut, ctb] (Reviews the documentation), Florian De Boissieu [ctb] (Fixed bugs and improved catalog features), Andrew Sánchez Meador [ctb] (Implemented wing2015() for segment_snags()), Bourdon Jean-François [ctb] (Contributed to Roussel2020() for track_sensor()), Gatziolis Demetrios [ctb] (Implemented Gatziolis2019() for track_sensor())

Initial release

2021-03-11