[GIS] Convert geographic coordinates to UTM zone 29N with Javascript

arcgis-javascript-apicoordinate systemjavascriptutm

I have an issue converting lat longs to UTM with the ArcGIS javscript API.

Lets say that I have a map, based on the UTM zone 29N, also known as WKID 32629.

I have a known set of coordinates from a GPS, in this format:

Latitude:  62.220596 
Longitude: -6.564331

The geograpic coordinates are in WKID 4326.

To convert using javascript I have been trying to use the Geometry Service's project method.

If we look at this post in the ArcGIS forum, it is about the same issue. Here, I have tried using the same code, and adjusting the wkid of the output spatialReference to 32629, and you see it returns only NaN, try in the JSfiddle to change the wkid to 4326, and you will see geographic coordinates.

Edit 1

Looking at the HTTP requests made to the server, I see this url is requested (now using the map of the Faroe Islands)

http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer/project?f=json&outSR=32629&inSR=4326&geometries={"geometryType":"esriGeometryPoint","geometries":[{"x":62.01387,"y":-6.7866,"spatialReference":{"wkid":4326}}]}&callback=dojo.io.script.jsonp_dojoIoScript2._jsonpCallback

This looks like a correct url, containing outSR, inSR, geometries, and callback. However, simulating requests to this url gives me either a 500 Internal Server Error, or this string:

dojo.io.script.jsonp_dojoIoScript2._jsonpCallback({"error":{"code":400,"message":"Unable to complete Project operation.","details":["Error projecting geometries"]}});

Any ideas?

Best Answer

I haven't looked at your code, but in the URL you provided, your X and Y are flipped around. For Faroe Islands, X should be -6.7866 (longitude) while Y should be 62.01387 (latitude). Here's a working URL of what you're trying to do:

http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer/project?f=json&outSR=32629&inSR=4326&geometries={"geometryType":"esriGeometryPoint","geometries":[{"x":-6.7866,"y":62.01387,"spatialReference":{"wkid":4326}}]}&callback=dojo.io.script.jsonp_dojoIoScript2._jsonpCallback

That correctly returns:

dojo.io.script.jsonp_dojoIoScript2._jsonpCallback({"geometryType":"esriGeometryPoint","geometries":[{"x":615863.053581134,"y":6877701.89119242}]});

As for 500s, I seem to get those quite frequently with sampleserver3 as well tonight. Try using sampleserver1 instead, that one seems to be more stable.

Related Solutions

[GIS] Get XY coordinates in UTM from web-mercator where UTM zone is not known

This is how you change it to UTM, First you have yo change it to wgs, and then call the function to do the rest

  function showCoordinates(evt) {
     var wgs = webMercatorUtils.webMercatorToGeographic(evt.mapPoint);
                var mp = evt.mapPoint;
                // Converting The WGS to UTM
                document.getElementById("utmCoordinates").innerHTML = myFunction(wgs.x, wgs.y);
                function myFunction(lan1, fi)

 {

                var a = 6378137.000;
                var b = 6356752.314;
                var f = (a - b) / a;
                var e2 = Math.sqrt((Math.pow(a, 2) - Math.pow(b, 2)) / Math.pow(b, 2));
                var e = Math.sqrt((Math.pow(a, 2) - Math.pow(b, 2)) / Math.pow(a, 2));

                var zone;
                var lan0;
                if (lan1 > 0) {
                    var zone = 30 + Math.ceil(lan1 / 6);
                    lan0 = Math.floor(lan1 / 6) * 6 + 3;
                }
                else {
                    var zone = 30 - Math.floor(Math.abs(lan1) / 6);
                    lan0 = -Math.floor(Math.abs(lan1) / 6) * 6 - 3;
                }


                //-----------------------------------------------

                var lan = lan1 - lan0;
                lan = lan * Math.PI / 180;
                fi = fi * Math.PI / 180;
                var N = a / Math.pow(1 - Math.pow(e, 2) * Math.pow(Math.sin(fi), 2), 0.5);
                var M = a * (1 - Math.pow(e, 2)) / Math.pow((1 - (Math.pow(e, 2) * Math.pow(Math.sin(fi), 2))), (3 / 2));
                var t = Math.tan(fi);
                var p = N / M;

                //----------------------------------------------
                var k0 = 0.9996;

                var term1 = Math.pow(lan, 2) * p * Math.pow(Math.cos(fi), 2) / 2;
                var term2 = Math.pow(lan, 4) * Math.pow(Math.cos(fi), 4) * (4 * Math.pow(p, 3) * (1 - 6 * Math.pow(t, 2)) + Math.pow(p, 2) * (1 + 24 * Math.pow(t, 2)) - 4 * p * Math.pow(t, 2)) / 24;
                var term3 = Math.pow(lan, 6) * Math.pow(Math.cos(fi), 6) * (61 - 148 * Math.pow(t, 2) + 16 * Math.pow(t, 4)) / 720;

                var Kutm = k0 * (term1 + term2 + term3);


                //----------------------------------------------
                term1 = Math.pow(lan, 2) * p * Math.pow(Math.cos(fi), 2) * (p - Math.pow(t, 2)) / 6;
                term2 = Math.pow(lan, 4) * Math.pow(Math.cos(fi), 4) * (4 * Math.pow(p, 3) * (1 - 6 * Math.pow(t, 2)) + Math.pow(p, 2) * (1 + 8 * Math.pow(t, 2)) - Math.pow(p, 2) * Math.pow(t, 2) + Math.pow(t, 4)) / 120;
                term3 = Math.pow(lan, 6) * Math.pow(Math.cos(fi), 6) * (61 - 479 * Math.pow(t, 2) + 179 * Math.pow(t, 4) - Math.pow(t, 6)) / 5040;

                var Xutm = 500000 + k0 * lan * N * Math.cos(fi) * (1 + term1 + term2 + term3);

                //----------------------------------------------

                var A0 = 1 - 0.25 * Math.pow(e, 2) - 3 / 64 * Math.pow(e, 4) - 5 / 256 * Math.pow(e, 6);
                var A2 = 3 / 8 * (Math.pow(e, 2) + 0.25 * Math.pow(e, 4) + 15 / 128 * Math.pow(e, 6));
                var A4 = 15 / 256 * (Math.pow(e, 4) + 0.75 * Math.pow(e, 6));
                var A6 = 35 / 3072 * Math.pow(e, 6);

                var sfi = a * (A0 * fi - A2 * Math.sin(2 * fi) + A4 * Math.sin(4 * fi) - A6 * Math.sin(6 * fi));

                //----------------------------------------------

                term1 = Math.pow(lan, 2) * N * Math.sin(fi) * Math.cos(fi) / 2;
                term2 = Math.pow(lan, 4) * N * Math.sin(fi) * Math.pow(Math.cos(fi), 3) * (4 * Math.pow(p, 2) + p - Math.pow(t, 2)) / 24;
                term3 = Math.pow(lan, 6) * N * Math.sin(fi) * Math.pow(Math.cos(fi), 5) * (8 * Math.pow(p, 4) * (11 - 24 * Math.pow(t, 2)) - 28 * Math.pow(p, 3) * (1 - 6 * Math.pow(t, 2)) + Math.pow(p, 2) * (1 - 32 * Math.pow(t, 2)) - p * 2 * Math.pow(t, 2) + Math.pow(t, 4));
                var term4 = Math.pow(lan, 8) * N * Math.sin(fi) * Math.pow(Math.cos(fi), 7) * (1385 - 3111 * Math.pow(t, 2) + 543 * Math.pow(t, 4) - Math.pow(t, 6));

                var Yutm = k0 * (sfi + term1 + term2 + term3 + term4);
                UTMx = Xutm.toFixed(5);
                UTMy = Yutm.toFixed(5);
                return (Xutm.toFixed(5).toString() + "," + Yutm.toFixed(5).toString());

                //return Xutm.toString().concat(" ; " + Yutm.toString() + " " + zone.toString());
            }

[GIS] EPSG code for UTM zone

The UTM zones and their respective EPSG codes cover the whole area of their respecive zone from the equator to 84N / 80S. These areas are subdivided by the letters from South to North, and these again are subdivided into 100km grid squares, but the projection system is not affected by these subdivisions. Hence for 29U you can use EPSG:32629.

For areas above 84N / below 80S you should use the Universal Polar Stereographic coordinate system.

Best Answer

Related Solutions

[GIS] Get XY coordinates in UTM from web-mercator where UTM zone is not known

[GIS] EPSG code for UTM zone

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