Open data set of government-released address nodes
The default coordinate system is TWD97 (EPSG:3826). The axes are easting (CSV column: x or x_3826) and northing (CSV column: y<
585B
/code> or y_3826).
The coordinates can be converted to latitude and longitude (WGS 84, EPSG:4326). Use the transformation descriptions at the bottom of this page: https://epsg.io/3826
Here is a TypeScript example:
import proj4 from 'proj4';
proj4.defs('EPSG:3826', '+proj=tmerc +lat_0=0 +lon_0=121 +k=0.9999 +x_0=250000 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs +type=crs');
/**
* Convert from EPSG:3826 (TWD97) to EPSG:4326 (WGS 84)
*/
function convertTWD97toWGS84(x: number, y: number) {
const [longitude, latitude] = proj4('EPSG:3826', proj4.WGS84, [x, y]);
return { latitude, longitude };
}