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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/coords.R
\name{wkb_coords}
\alias{wkb_coords}
\alias{wkt_coords}
\title{Extract coordinates from well-known geometries}
\usage{
wkb_coords(wkb, sep_na = FALSE)
wkt_coords(wkt, sep_na = FALSE)
}
\arguments{
\item{wkb}{A \code{list()} of \code{\link[=raw]{raw()}} vectors, such as that
returned by \code{sf::st_as_binary()}.}
\item{sep_na}{Use \code{TRUE} to separate geometries and linear
rings with a row of \code{NA}s. This is useful for generating
output that can be fed directly to \code{\link[graphics:polypath]{graphics::polypath()}}
or \code{\link[graphics:lines]{graphics::lines()}} without modification.}
\item{wkt}{A character vector containing well-known text.}
}
\value{
A data.frame with columns:
\itemize{
\item \code{feature_id}: The index of the top-level feature
\item \code{part_id}: The part identifier, guaranteed to be unique for every simple geometry
(including those contained within a multi-geometry or collection)
\item \code{ring_id}: The ring identifier, guaranteed to be unique for every ring.
\item \code{x}, \code{y}, \code{z}, \code{m}: Coordinaate values (both absence and \code{nan} are recorded
as \code{NA})
}
}
\description{
These functions are optimised for graphics output,
which in R require flat coordinate structures. See
\code{\link[graphics:points]{graphics::points()}}, \code{\link[graphics:lines]{graphics::lines()}},
and \code{\link[graphics:polypath]{graphics::polypath()}} for how to send these
to a graphics device, or \code{\link[grid:grid.points]{grid::pointsGrob()}},
\code{\link[grid:grid.lines]{grid::linesGrob()}}, and \code{\link[grid:grid.path]{grid::pathGrob()}} for how
to create graphical objects using this output.
}
\examples{
text <- c("LINESTRING (0 1, 19 27)", "LINESTRING (-1 -1, 4 10)")
wkt_coords(text)
wkt_coords(text, sep_na = TRUE)
}
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