Calculate centroid of a point cloud

Usage

centroid(x, ...)

# S4 method for class 'matrix'
centroid(
  x,
  long = NULL,
  lat = NULL,
  duplicates = FALSE,
  plot = FALSE,
  plot.args = NULL
)

# S4 method for class 'data.frame'
centroid(
  x,
  tax = NULL,
  long = "long",
  lat = "lat",
  duplicates = FALSE,
  plot = FALSE,
  plot.args = NULL
)

Arguments

x: Eiher a 2-column numeric matrix with two columns: longitudes and latitudes, or a data.frame with these columns.
...: Additional arguments passed to class-specific methods.
long: character, column name of the longitudes.
lat: character, column name of the latitudes.
duplicates: logical, should identical coordinates be included in the calculation (default is FALSE).
plot: Logical, should the result be plotted? Will plot over active plot (as in add=TRUE), if here is any.
plot.args: List arguments passed to the plotting function: points.
tax: character, used only in the data.frame method. Column name of groups (e.g. taxa) that allows the iteration of the method for multiple groups.

Value

Either a single numeric or a list with an estimate and other information.

Examples

# Records
data(pinna)
nobilis <- pinna[pinna$species=="Pinna nobilis", ]
plot(nobilis[c("decimalLongitude", "decimalLatitude")], pch=16, col="#00BBAA66")

# Number of unique coordinate pairs
cent <- centroid(nobilis, long="decimalLongitude", lat="decimalLatitude")

points(cent[1], cent[2], col="darkred", pch=3, lwd=4, cex=4)