wk_vertices.Rd

% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/vertex-filter.R
\name{wk_vertices}
\alias{wk_vertices}
\alias{wk_coords}
\alias{wk_coords<-}
\alias{wk_vertex_filter}
\title{Extract vertices}
\usage{
wk_vertices(handleable, ...)

wk_coords(handleable, ...)

wk_coords(handleable, use_z = NA, use_m = NA) <- value

wk_vertex_filter(handler, add_details = FALSE)
}
\arguments{
\item{handleable}{A geometry vector (e.g., \code{\link[=wkb]{wkb()}}, \code{\link[=wkt]{wkt()}}, \code{\link[=xy]{xy()}},
\code{\link[=rct]{rct()}}, or \code{\link[sf:sfc]{sf::st_sfc()}}) for which \code{\link[=wk_handle]{wk_handle()}} is defined.}

\item{...}{Passed to the \code{\link[=wk_handle]{wk_handle()}} method.}

\item{use_z, use_m}{Used to declare the output type. Use \code{TRUE} to
ensure the output has that dimension, \code{FALSE} to ensure it does not,
and \code{NA} to leave the dimension unchanged.}

\item{value}{An \code{\link[=xy]{xy()}}, \code{\link[=xyz]{xyz()}}, \code{\link[=xym]{xym()}}, or \code{\link[=xyzm]{xyzm()}} of coordinates
used to replace values in the input. Use \code{NA} to keep the existing
value.}

\item{handler}{A \link[=wk_handle]{wk_handler} object.}

\item{add_details}{Use \code{TRUE} to add a "wk_details" attribute, which
contains columns \code{feature_id}, \code{part_id}, and \code{ring_id}.}
}
\value{
\itemize{
\item \code{wk_vertices()} extracts vertices and returns the in the same format as
the handler
\item \code{wk_coords()} returns a data frame with columns columns \code{feature_id}
(the index of the feature from whence it came), \code{part_id} (an arbitrary
integer identifying the point, line, or polygon from whence it came),
\code{ring_id} (an arbitrary integer identifying individual rings within
polygons), and one column per coordinate (\code{x}, \code{y}, and/or \code{z} and/or \code{m}).
}
}
\description{
These functions provide ways to extract individual coordinate values.
Whereas \code{wk_vertices()} returns a vector of coordinates as in the same
format as the input, \code{wk_coords()} returns a data frame with coordinates
as columns.
}
\details{
\verb{wk_coords<-} is the replacement-function version of 'wk_coords'.
Using the engine of \code{\link[=wk_trans_explicit]{wk_trans_explicit()}} the coordinates of an object
can be transformed in a generic way using R functions as needed.
}
\examples{
wk_vertices(wkt("LINESTRING (0 0, 1 1)"))
wk_coords(wkt("LINESTRING (0 0, 1 1)"))

# wk_coords() replacement function
x <- xy(1:5, 1:5)
y <- as_wkt(x)
wk_coords(y) <- cbind(5:1, 0:4)
wk_coords(x) <- y[5:1]
y
x

}