lets.presab {letsR} | R Documentation |
Create a presence-absence matrix of species' geographic ranges within a grid
Description
Convert species' ranges (in shapefile format) into a presence-absence matrix based on a user-defined grid system
Usage
lets.presab(
shapes,
xmn = NULL,
xmx = NULL,
ymn = NULL,
ymx = NULL,
resol = NULL,
remove.cells = TRUE,
remove.sp = TRUE,
show.matrix = FALSE,
crs = "+proj=longlat +datum=WGS84",
crs.grid = crs,
cover = 0,
presence = NULL,
origin = NULL,
seasonal = NULL,
count = FALSE
)
Arguments
shapes |
Object of class |
xmn |
Minimun longitude used to construct the grid in which the matrix will be based (i.e. the [gridded] geographic domain of interest). If NULL, limits will be calculated based on the limits of the shapes object. |
xmx |
Maximun longitude used to construct the grid in which the matrix will be based (i.e. the [gridded] geographic domain of interest). If NULL, limits will be calculated based on the limits of the shapes object. |
ymn |
Minimun latitude used to construct the grid in which the matrix will be based (i.e. the [gridded] geographic domain of interest). If NULL, limits will be calculated based on the limits of the shapes object. |
ymx |
Maximun latitude used to construct the grid in which the matrix will be based (i.e. the [gridded] geographic domain of interest). If NULL, limits will be calculated based on the limits of the shapes object. |
resol |
Numeric vector of length 1 or 2 to set the grid resolution. If NULL, resolution will be equivalent to 1 degree of latitude and longitude. |
remove.cells |
Logical, if |
remove.sp |
Logical, if |
show.matrix |
Logical, if |
crs |
Character representing the PROJ.4 type description of a Coordinate Reference System (map projection) of the polygons. |
crs.grid |
Character representing the PROJ.4 type description of a Coordinate Reference System (map projection) for the grid. Note that when you change this options you may probably change the extent coordinates and the resolution. |
cover |
Percentage of the cell covered by the shapefile that will be considered for presence (values between 0 and 1). |
presence |
A vector with the code numbers for the presence type to be considered in the process (for IUCN spatial data https://www.iucnredlist.org/resources/spatial-data-download, see metadata). |
origin |
A vector with the code numbers for the origin type to be considered in the process (for IUCN spatial data). |
seasonal |
A vector with the code numbers for the seasonal type to be considered in the process (for IUCN spatial data). |
count |
Logical, if |
Details
The function creates the presence-absence matrix based on a raster
object. Depending on the cell size, extension used and number of species it
may require a lot of memory, and may take some time to process it. Thus,
during the process, if count
argument is set TRUE
, a counting
window will open so you can see the progress (i.e. in what polygon/shapefile
the function is working). Note that the number of polygons is not the same
as the number of species that you have (i.e. a species may have more than
one polygon/shapefiles).
Value
The result is a list object of class PresenceAbsence
with the following objects: Presence-Absence Matrix: A matrix of
species' presence(1) and absence(0) information. The first two columns
contain the longitude (x) and latitude (y) of the cells' centroid (from the
gridded domain used); Richness Raster: A raster containing species
richness data; Species name: A character vector with species' names
contained in the matrix.
*But see the optional argument show.matrix
.
Author(s)
Bruno Vilela & Fabricio Villalobos
See Also
Examples
## Not run:
# Spatial distribution polygons of south american frogs
# of genus Phyllomedusa.
data(Phyllomedusa)
PAM <- lets.presab(Phyllomedusa)
summary(PAM)
# Species richness map
plot(PAM, xlab = "Longitude", ylab = "Latitude",
main = "Phyllomedusa species richness")
# Map of the specific species
plot(PAM, name = "Phyllomedusa nordestina")
## End(Not run)