spMakeSpatialPoints {FIESTA} | R Documentation |
Generates an S4 SpatialPoints object with defined projection from a data table or matrix including X and Y coordinates, with option to export as an ArcGIS shapefile (*.shp).
spMakeSpatialPoints(
xyplt,
xyplt_dsn = NULL,
xy.uniqueid = NULL,
xvar = NULL,
yvar = NULL,
xy.crs = 4269,
prj = NULL,
datum = NULL,
zone = NULL,
zoneS = FALSE,
aea.param = "USGS",
addxy = FALSE,
exportsp = FALSE,
savedata_opts = NULL
)
xyplt |
Data frame object or String. Name of layer with xy coordinates and unique identifier. Can be layer with xy_dsn, full pathname, including extension, or file name (with extension) in xy_dsn folder. |
xyplt_dsn |
String. Name of database or folder were xyplt is. The dsn varies by driver. See gdal OGR vector formats (https://www.gdal.org/ogr_formats.html). |
xy.uniqueid |
String. Unique identifier of xyplt rows. |
xvar |
String. Name of variable in xyplt defining x coordinate. |
yvar |
String. Name of variable in xyplt defining y coordinate. |
xy.crs |
PROJ.4 String or CRS object or Integer EPSG code defining Coordinate Reference System. (e.g., EPSG:4269-Geodetic coordinate system for North America, NAD83). |
prj |
String. Projection, or coordinate system of the X/Y coordinates ("longlat", "utm", "aea"). If other, include PROJ.4 string in prj4str. |
datum |
String. Datum of projection ("WGS84", "NAD83", "NAD27"). |
zone |
Integer. If prj="utm", the UTM zone. |
zoneS |
Logical. If prj="utm", if the UTM zone is in the Southern hemisphere. |
aea.param |
String. If prj="aea", the associated lat/lon parameters (USGS: " +lat_1=29.5 +lat_2=45.5 +lat_0=23 +lon_0=-96 +x_0=0 +y_0=0"). If other, include PROJ.4 string in prj4str. |
addxy |
Logical. If TRUE, adds x and y variables to spatial sf object. |
exportsp |
Logical. If TRUE, exports spatial object. |
savedata_opts |
List. See help(savedata_options()) for a list of options. Only used when exportsp = TRUE. |
spplt |
sf obect with spatial points and defined CRS. |
If exportsp = TRUE, the sf object is written to specified output.
If exportsp=TRUE and a shp output format is specified:
The ESRI
shapefile driver truncates variable names to 10 characters or less.
Variable names are changed before export using an internal function
(trunc10shp). Name changes are output to the outfolder,
'outshpnm'_newnames.csv. The returned Spatial object will have original
names, before truncating.
If Spatial object has more than 1 record, it cannot be exported.
Common Datums and associated spheroid (ellipsoid):
NAD27 - North American
Datum of 1927 - Clarke 1866 spheroid
NAD83 - North American Datum of 1983
- GRS 1980 spheroid
WGS84 - World Geodetic System of 1984 - WGS 1984
spheroid
Tracey S. Frescino
# Generate an `sf` points object with `spMakeSpatialPoints` for Wyoming plot
# data, stored in `FIESTA`
spMakeSpatialPoints(xyplt = WYplt,
xy.uniqueid = "CN",
xvar = "LON_PUBLIC",
yvar = "LAT_PUBLIC",
prj = "longlat",
datum = "NAD83")