showWKT: Show Well-Known Text spatial reference system metadata

In rgdal: Bindings for the 'Geospatial' Data Abstraction Library

Show Well-Known Text spatial reference system metadata

Description

In modern workflows with PROJ >= 6 and GDAL >= 3, use only showSRID() DEPRECATED: Use GDAL/OGR spatial reference objects to convert a PROJ.4 representation to a Well-Known Text representation, and report an EPSG code if it can be determined by OGR SRS services.

Usage

showP4(wkt, morphFromESRI=FALSE, enforce_xy = NULL)
showSRID(inSRID, format="WKT2", multiline="NO", enforce_xy = NULL, EPSG_to_init=TRUE,
 prefer_proj=NULL)
get_P6_datum_hard_fail()
set_P6_datum_hard_fail(value)
get_thin_PROJ6_warnings()
set_thin_PROJ6_warnings(value)
get_prefer_proj()
set_prefer_proj(value)
get_rgdal_show_exportToProj4_warnings()
set_rgdal_show_exportToProj4_warnings(value)
get_PROJ6_warnings_count()
OSRIsProjected(obj)

Arguments

enforce_xy	(PROJ6+/GDAL3+) either use global setting (default NULL) or override policy for coordinate ordering easting/x as first axis, northing/y as second axis.
wkt	A valid WKT character string representing a spatial reference system
morphFromESRI	default TRUE, morph the WKT string from the representation used by ESRI
inSRID	Input coordinate reference string
obj	valid CRS object
format	Output format, default WKT2
multiline	Multiline output, either "NO" or "YES"
EPSG_to_init	default TRUE, workaround for PROJ 6.3.0 frailty leading to the dropping of +ellps= and +units=; DATUM seems to disappear in the internal definition
prefer_proj	default NULL, if TRUE, use PROJ compiled code directly, rather than FALSE using PROJ via GDAL SRS; if NULL, uses value shown by get_prefer_proj() set on startup to TRUE.

value

a logical value. For set_P6_datum_hard_fail(): by default, a deprecated/ignored input DATUM key/value pair on reading a file with PROJ6 will give a warning (default FALSE); if TRUE, an error is triggered, which may be trapped using try. For set_thin_PROJ6_warnings() default FALSE, can be set to TRUE to report only once and count the number of non-issues warnings, retrieved by get_PROJ6_warnings_count(). For set_rgdal_show_exportToProj4_warnings(), default in rgdal version 1.5.* TRUE, from 1.6 FALSE. The options("rgdal_show_exportToProj4_warnings"="x") may be used before loading rgdal to set the internal logical variables; if the option is set to "all", all warnings reporting CRS degradation stemming from the GDAL OSR function exportToProj4() even if trivial are reported; if set to "thin", all warnings are detected but thinned so that one report is given per function call; if set to "none", the degradations are detected but not reported.

Value

For showWKT, a character string containing the WKT representation of the PROJ.4 string.

Note

The options("rgdal_show_exportToProj4_warnings"="x") may be used before loading rgdal to set the internal logical variables; if the option is set to "all", all warnings reporting CRS degradation stemming from the GDAL OSR function exportToProj4() even if trivial are reported; if set to "thin", all warnings are detected but thinned so that one report is given per function call; if set to "none", the degradations are detected but not reported.

Author(s)

Roger Bivand

References

https://gdal.org/tutorials/osr_api_tut.html

See Also

is.projected, CRS-class

Examples

set_thin_PROJ6_warnings(TRUE)
cities <- readOGR(system.file("vectors", package = "rgdal")[1], "cities")
readLines(system.file("vectors/cities.prj", package = "rgdal")[1])
showP4(showWKT("+init=epsg:28992"))
exts <- rgdal_extSoftVersion()
run <- new_proj_and_gdal()
if (run) {
  cat(showSRID("EPSG:27700", multiline="YES"), "\n")
}
if (run) {
(prj <- showSRID("EPSG:27700", "PROJ"))
}
if (run) {
showSRID(paste0(prj, " +datum=OSGB36"), "WKT1")
}
if (run) {
showSRID(paste0(prj, " +towgs84=370.936,-108.938,435.682"), "WKT1")
}
if (run) {
showSRID(paste0(prj, " +nadgrids=OSTN15_NTv2_OSGBtoETRS.gsb"), "WKT1")
}
if (run) {
showSRID(paste0(prj, " +datum=OSGB36"), "WKT2")
}
if (run) {
showSRID(paste0(prj, " +towgs84=370.936,-108.938,435.682"), "WKT2")
}
if (run) {
showSRID(paste0(prj, " +nadgrids=OSTN15_NTv2_OSGBtoETRS.gsb"), "WKT2")
}
if (run) {
showSRID("ESRI:102761", "WKT2")
}
if (run) {
showSRID("OGC:CRS84", "WKT2")
}
if (run) {
showSRID("urn:ogc:def:crs:OGC:1.3:CRS84", "WKT2")
}
if (run) {
try(showSRID("", "WKT2"))
}

OSRIsProjected(CRS("+proj=longlat"))
OSRIsProjected(CRS("+proj=geocent"))
OSRIsProjected(CRS("+proj=geocent +units=km"))

rgdal documentation built on June 7, 2023, 5:09 p.m.