Say I have the coordinates: N: 5413457.7 E: 1528677.3
If I were to add 10 to the northing value would that make the new coordinates point 10 meters north of the original point?
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Yes, but to explain why:
I can tell that you have projected coordinates (as I assume you're in New Zealand) the numbers are quite large, much bigger than -180 to 180, which is probably New Zealand Transverse Mercator 2000:
Projection type:Transverse Mercator Reference ellipsoid:GRS80 Datum:NZGD2000 Origin latitude:0° 00' 00" South Origin longitude / central meridan:173° 00' 00" East False Northing:10,000,000 metres North False Easting:1,600,000 metres EastCentral meridian scale factor:0.9996 - See more at:
Which is in metres, so you can add 10 to go 10 metres north... approximately. Zones are slightly banana shaped so it's not a true north but roundabout. You can expect to be within a few centimetres of the correct location; the larger the displacement and the further from the centre of the zone the more you are likely to be off.
To get a more accurate figure use software like GDAL/OGR (OGR is for points, GDAL is for raster but they're distributed in the same package); GDAL uses the PROJ.4 library for coordinate transformation. This is open source software so is free to use. It's been a while since I've done OGR and I think it goes a little like this:
OGRpoint myPoint = new OGRPoint(Xcoord,Ycoord); OGRSpatialReference fromSR = new OGRSpatialReference(); fromSR.importFromEPSG(2193); // NZTM is 2193, WGS84 UTM 59 south is 32759 OGRSpatialReference toSR = new OGRSpatialReference(); toSR.importFromEPSG(32759); OGRGeometry myGeom = (OGRGeometry) myPoint; myGeom.assignSpatialReference(fromSR); // assign the spatial reference myGeom.transformTo(toSR); // convert to the 'to' spatial reference myPoint = (OGRpoint) myGeom; outX = myPoint.getX(); outY = myPoint.getY();
This is more accurate than simply adjusting the X and Y... WGS84/Geographic is EPSG:4326.