 | CIPJSetGXF Method |
Set coordinate system from GXF style strings.
Namespace:
GeoEngine.Core.GXNetX
Assembly:
geoengine.core.gxnetx (in geoengine.core.gxnetx.dll) Version: 2024.2.0.25
Syntaxpublic void SetGXF(
string str1,
string str2,
string str3,
string str4,
string str5
)
public void SetGXF(
string str1,
string str2,
string str3,
string str4,
string str5
)
Public Sub SetGXF (
str1 As String,
str2 As String,
str3 As String,
str4 As String,
str5 As String
)
Public Sub SetGXF (
str1 As String,
str2 As String,
str3 As String,
str4 As String,
str5 As String
)
public:
void SetGXF(
String^ str1,
String^ str2,
String^ str3,
String^ str4,
String^ str5
)
public:
void SetGXF(
String^ str1,
String^ str2,
String^ str3,
String^ str4,
String^ str5
)
member SetGXF :
str1 : string *
str2 : string *
str3 : string *
str4 : string *
str5 : string -> unit
member SetGXF :
str1 : string *
str2 : string *
str3 : string *
str4 : string *
str5 : string -> unit
Parameters
- str1
- Type: SystemString
"projection name" or PCS_NAME from ipj_pcs.csv (datum / projection) or EPSG coordinate system code number or "<file.prj>" projection file name or "<file.wrp>" warp file name - str2
- Type: SystemString
"datum name"[, major axis, elipticity, prime meridian] or DATUM from datum.csv or EPSG datum code number - str3
- Type: SystemString
"method name", parameters (P1 through P8) or "projection name"[,"method name","Units",P1,P2...] or TRANSFORM from transform.csv or EPSG transform method code number - str4
- Type: SystemString
"unit name", convertion to metres or UNIT_LENGTH from units.csv - str5
- Type: SystemString
"local transform name"[,dX,dY,dZ,rX,rY,rZ,Scale] or DATUM_TRF from datumtrf.csv or AREA_OF_USE from ldatum.csv or EPSG local datum transform code number
Remarks
Simplest Usage:
The coordinate system can be resolved from the "coordinate system name"
if the name is specified using an EPSG number or naming convention such as:
"datum / projection" (example: "Arc 1960 / UTM zone 37S")
Where:
"datum" is the EPSG datum name (eg. NAD83). All supported datums are
listed in ...usercsvdatum.csv.
"projection" is the EPSG coordinate system map projection.
datum name (eg. "UTM zone 10N"). All supported coordinate
system projections are listed in ...user/csv/transform.csv.
All EPSG known combined coordinate systems of the earth are
listed in ...user/csv/ipj_pcs.csv.
To define a geographic (longitude, latitude) oordinate system, specify
the datum name alone (ie "Arc 1960"). EPSG numbers can also be used, so in
the example above the name can be "21037".
The coordinate system may also be oriented arbitrarily in 3D relative to
the base coordinate system by specifying the orientation as a set of
6 comma-separated values between angled brackets after the coordinate
system name, e.g:
::
"datum / projection"<oX,oY,oZ,rX,rY,rZ>
21037<oX,oY,oZ,rX,rY,rZ>
where:
oX,oY,oZ is the location of the local origin on the CS
rX,rY,rZ are rotations in degrees azimuth (clockwise) of
the local axis frame around the X, Y and Z axis
respectively. A simple plane rotation will only have
a rotation around Z.
For example:
::
"Arc 1960 / UTM zone 37S"<525000,2500000,0,0,0,15>
defines a local system with origin at (525000,2500000)
with a rotation of 15 degrees azimuth.
Orientation parameters not defined will default to align with the
base CS, Note that although allowed, it does not make sense to have
an orientation on a geographic coordinate system (long,lat).
Complete usage:
A coordinate system can also be fully described by providing an additional
four strings that define the datum, map projection, length units and
prefered local datum transform. Refer to GXF revision 3 for further detail:
http://www.geosoft.com/resources/goto/GXF-Grid-eXchange-File
Note that coordinate system reference tables sre maintained in csv files
located in the .../user/csv folder found with the Geosoft installation files,
which will usually be located here:
C:\Program Files (x86)\Geosoft\Oasis montaj\user\csv
The "datum" string can use a datum name defined in the "datum.csv" file,
or the local datum name from datumtrf.csv, or the local datum description
from ldatum.csv.
For a non-EPSG datum, you can define your own datum parameters in the
Datum stringfield as follows:
::
"*YourDatumName",major_axis,flattening(or eccentricity)[,prime_meridian]
where
The * before "YourDatumName" indicates this is a non-EPSG name.
major_axis is in metres.
flattening less than 0 is interpreted as eccentricity (0 indicates a sphere).
prime_meridian is optional, specified in degrees of longitude relative to
Greenwich.
The "Projection" can contain a projection system defined in the
"transform.csv" file, or the name of a projection type followed by projection
parameters. Geographic coordinates systems (long/lat only) must leave
"projection" blank.
Projection names not defined in "transform.csv" can be defined in the
"projection" string as follows:
::
method,length_units,P1,P2,...
where:
method
is a method from the table "transform_parameters.csv".
length_units
is a "Unit_length" from units.csv.
P1 through P8 (or fewer) are the projection parameters for the method
as defined in "transform_parameters.csv", and in the order defined.
Parameters that are blank in "transform_parameters.csv" are omitted
from the list so that each method will have a minimum list of
parameters.
Angular parameters must always be degrees, and may be defined a
decimal degree fromat, or "DEG.MM.SS.ssss".
Distance parameters (False Northing and False Easting) must be
defined in the "length_units" (string 4).
Examples:
::
Geographic long,lat on datum "Arc 1960":
"4210","","","",""
"Arc 1960","","","",""
"","Arc 1960","","",""
Projected Coordinate System, UTM zone 37S
"21037","","","",""
"","4210","16137","",""
""Arc 1960 / UTM zone 37S"","","","",""
"",""Arc 1960"","UTM zone 37S","",""
"",""Arc 1960"","UTM zone 37S","m",""
"",""Arc 1960"","UTM zone 37S","m,1.0",""
"",""Arc 1960"","UTM zone 37S","m,1.0","");
"",""Arc 1960"","UTM zone 37S","m","Arc 1960 to WGS 84 (1)"
Locally oriented coordinate system (origin at 525000,2500000, rotated 15 deg):
"21037<525000,2500000,0,0,0,15>","","","",""
"<525000,2500000,0,0,0,15>","4210","16137","",""
""Arc 1960 / UTM zone 37S"<525000,2500000,0,0,0,15>","","","",""
See Also