fk89 to wgs84

General talk
1

Can someone please help me convert fk89 to wgs84

i have absolute no idea on how to do this

if you dont know what fk89 is then try to look at this
http://www.us.fo/Default.aspx?ID=5599
it is in Faroese but you should get the idea

/LiFo

2

A quick lookup in the EPSG database says that is might be EPSG:4753 you want, try it out with openlayers:

# fk89
<4753> +proj=longlat +ellps=intl +no_defs  <>

This guy tries to display a file with WGS 84 lon/lat on openlayers, just change “EPGS:4326” and you can load your points…

            var pois = new OpenLayers.Layer.Text( "My Points", { location:"./textfile.txt", projection: new OpenLayers.Projection("EPSG:4326")} );
3

Sorry for the delayed replay
it might well be “EPSG:4326” i don’t konw, and dont realy know how to use that code you gave
have tryed to fiddle with openlayers but cant get it to work

if we take the position in fk89 or fd54 703338.38 / 583150.34
in wgs84 it is approximate 62.01276 / -6.774199

and i was more looking for a formula or a library to convert between them

4

proj.4 is a good tool it all depends on what you use.

5

Hi,

Do you have data in some GIS-format and FK89? If that is the case then ogr2ogr is your tool.
For example command
ogr2ogr -f “ESRI Shapefile” -s_srs epsg:4753 -t_srs epsg:4326 output.shp input.shp
would convert shapefile from fk89 to wgs84

6

They seem to publish in dxf forma, which isn’t supported by ogr2ogr. They seem to charge pretty hefty license sum for their data, are you sure this is free data you want to use?

7

it is not there dxf data i was thinking about
weel yes just one file that is freely available it is the outline of the ilands

the data i was thinking about is “House numbers on streets” the data is in a custom text file

i played around with Proj.NET
but could not get it to make the right conversion

it think it is becouse i lack a general understanding about geografic and projection kordinate systems

this is my experiment

string wkt = “GEOGCS["FD54",DATUM["Faroe_Datum_1954",SPHEROID["International 1924",6378388,297,AUTHORITY["EPSG","7022"]],AUTHORITY["EPSG","6741"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4741"]]”;

    CoordinateTransformationFactory ctfac = new CoordinateTransformationFactory();        
    GeographicCoordinateSystem wgs84 = GeographicCoordinateSystem.WGS84;        
    IGeographicCoordinateSystem gcs = CoordinateSystemWktReader.Parse(wkt) as IGeographicCoordinateSystem;        
    
    ICoordinateTransformation trans = ctfac.CreateFromCoordinateSystems( gcs, wgs84);
    
    double[] fromPoint = new double[]{701535,594920}; //toPoint should be 62N 7V or 6875795m,604743M
  
    double[] toPoint = trans.MathTransform.Transform(fromPoint);

    litdbg.Text = "val: " + toPoint[0] + "<br/>val:" + toPoint[1];
    // The result
    //val: 75,0000000000087
    //val:-19,9994708768688
8

Well I’ve only succeded with trial and error as you have. So I would just keep trying.

You seem to be converting from your custom WKT string to wgs84, correct?

9

Hi,
Two more alternatives:

  • cs2cs converts coordinate pairs from one coordinate system to another. With some scripting you could use that.
  • use ogr2ogr and use your text file as input as instructed here:
    http://gdal.org/ogr/drv_csv.html