平面坐标转大地坐标(经纬度),平面坐标转大地坐标

js大地坐标与经纬度坐标互转 //高斯投影坐标反算成经纬度function GaussToBL(X,Y){ let ProjNo; let ZoneWide; 带宽 let output = new Array(2); let longitude1,latitude1, longitude0, X0,Y0, xval,yval;//latitude0, let e1,e2,f,a, ee, NN, T,C, M, D,R,u,fai, iPI; iPI = 3.14159265358979324/180.0; 3.1415926535898/180.0; // a = 6378245.0; f = 1.0/298.3; //54年北京坐标系参数 a=6378140.0; f=1.0/298.257; //80年西安坐标系参数 ZoneWide = 6; 6度带宽 ProjNo = parseInt(X/1000000) ; //查找带号 longitude0 = (ProjNo-1) * ZoneWide + ZoneWide / 2; longitude0 = longitude0 * iPI ; //中央经线 X0 = ProjNo*1000000+500000; Y0 = 0; xval = X-X0; yval = Y-Y0; //带内大地坐标 e2 = 2*f-f*f; e1 = (1.0-Math.sqrt(1-e2))/(1.0+Math.sqrt(1-e2)); ee = e2/(1-e2); M = yval; u = M/(a*(1-e2/4-3*e2*e2/64-5*e2*e2*e2/256)); fai = u+(3*e1/2-27*e1*e1*e1/32)*Math.sin(2*u)+(21*e1*e1/16-55*e1*e1*e1*e1/32)*Math.sin(4*u) +(151*e1*e1*e1/96)* Math.sin(6*u)+(1097*e1*e1*e1*e1/512)*Math.sin(8*u); C = ee*Math.cos(fai)*Math.cos(fai); T = Math.tan(fai)*Math.tan(fai); NN = a/Math.sqrt(1.0-e2*Math.sin(fai)*Math.sin(fai)); R = a*(1-e2)/Math.sqrt((1-e2*Math.sin(fai)*Math.sin(fai))*(1-e2*Math.sin(fai)*Math.sin(fai))*(1-e2*Math.sin (fai)*Math.sin(fai))); D = xval/NN; //计算经度(Longitude) 纬度(Latitude) longitude1 = longitude0+(D-(1+2*T+C)*D*D*D/6+(5-2*C+28*T-3*C*C+8*ee+24*T*T)*D *D*D*D*D/120)/Math.cos(fai); latitude1 = fai -(NN*Math.tan(fai)/R)*(D*D/2-(5+3*T+10*C-4*C*C-9*ee)*D*D*D*D/24 +(61+90*T+298*C+45*T*T-256*ee-3*C*C)*D*D*D*D*D*D/720); //转换为度 DD output[0] = longitude1 / iPI; output[1] = latitude1 / iPI; return output;}//经纬度=>高斯投影function BLToGauss(longitude, latitude){ let ProjNo=0; let ZoneWide; 带宽 let ret=Array(2); let longitude1,latitude1, longitude0,latitude0, X0,Y0, xval,yval; let a,f, e2,ee, NN, T,C,A, M, iPI; iPI = 0.0174532925199433; 3.1415926535898/180.0; ZoneWide = 6; 6度带宽 // a=6378245.0; f=1.0/298.3; //54年北京坐标系参数 a=6378140.0; f=1/298.257; //80年西安坐标系参数 ProjNo = parseInt(longitude / ZoneWide) ; longitude0 = ProjNo * ZoneWide + ZoneWide / 2; longitude0 = longitude0 * iPI ; latitude0 = 0; longitude1 = longitude * iPI ; //经度转换为弧度 latitude1 = latitude * iPI ; //纬度转换为弧度 e2=2*f-f*f; ee=e2*(1.0-e2); NN=a/Math.sqrt(1.0-e2*Math.sin(latitude1)*Math.sin(latitude1)); T=Math.tan(latitude1)*Math.tan(latitude1); C=ee*Math.cos(latitude1)*Math.cos(latitude1); A=(longitude1-longitude0)*Math.cos(latitude1); M=a*((1-e2/4-3*e2*e2/64-5*e2*e2*e2/256)*latitude1-(3*e2/8+3*e2*e2/32+45*e2*e2 *e2/1024)*Math.sin(2*latitude1) +(15*e2*e2/256+45*e2*e2*e2/1024)*Math.sin(4*latitude1)-(35*e2*e2*e2/3072)*Math.sin(6*latitude1)); xval = NN*(A+(1-T+C)*A*A*A/6+(5-18*T+T*T+72*C-58*ee)*A*A*A*A*A/120); yval = M+NN*Math.tan(latitude1)*(A*A/2+(5-T+9*C+4*C*C)*A*A*A*A/24 +(61-58*T+T*T+600*C-330*ee)*A*A*A*A*A*A/720); X0 = 1000000*(ProjNo+1)+500000; Y0 = 0; xval = xval+X0; yval = yval+Y0; ret[0]=xval; ret[1]=yval; return ret;}export default { GaussToBL, BLToGauss,}