高斯投影正算

高斯投影正、反算代码

//高斯投影正、反算

//////6度带宽 54年北京坐标系

//高斯投影由经纬度(Unit:DD)反算大地坐标(含带号，Unit:Metres)

void GaussProjCal(double longitude, double latitude, double *X, double *Y)

{

int ProjNo=0; int ZoneWide; ////带宽

double longitude1,latitude1, longitude0,latitude0, X0,Y0, xval,yval;

double 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 = (int)(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/sqrt(1.0-e2*sin(latitude1)*sin(latitude1));

T=tan(latitude1)*tan(latitude1);

C=ee*cos(latitude1)*cos(latitude1);

A=(longitude1-longitude0)*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)*sin(2*latitude1)

+(15*e2*e2/256+45*e2*e2*e2/1024)*sin(4*latitude1)-(35*e2*e2*e2/30 72)*sin(6*l

atitude1));

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*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 = 1000000L*(ProjNo+1)+500000L;

Y0 = 0;

xval = xval+X0; yval = yval+Y0;

*X = xval;

*Y = yval;

}

//高斯投影由大地坐标(Unit:Metres)反算经纬度(Unit:DD)

void GaussProjInvCal(double X, double Y, double *longitude, double *latitude)

{

int ProjNo; int ZoneWide; ////带宽

double longitude1,latitude1, longitude0,latitude0, X0,Y0, xval,yval;

double e1,e2,f,a, ee, NN, T,C, M, D,R,u,fai, iPI;

iPI = 0.0174532925199433; ////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=1/298.257; //80年西安坐标系参数

ZoneWide = 6; ////6度带宽

ProjNo = (int)(X/1000000L) ; //查找带号

longitude0 = (ProjNo-1) * ZoneWide + ZoneWide / 2;

longitude0 = longitude0 * iPI ; //中央经线

X0 = ProjNo*1000000L+500000L;

Y0 = 0;

xval = X-X0; yval = Y-Y0; //带内大地坐标

e2 = 2*f-f*f;

e1 = (1.0-sqrt(1-e2))/(1.0+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)*sin(2*u)+(21*e1*e1/16-55*e1*e1*e1*e1/32)*si n(

4*u)

+(151*e1*e1*e1/96)*sin(6*u)+(1097*e1*e1*e1*e1/512)*sin(8*u);

C = ee*cos(fai)*cos(fai);

T = tan(fai)*tan(fai);

NN = a/sqrt(1.0-e2*sin(fai)*sin(fai));

R = a*(1-e2)/sqrt((1-e2*sin(fai)*sin(fai))*(1-e2*sin(fai)*sin(fai))*(1-e2 *sin

(fai)*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)/cos(fai);

latitude1 = fai -(NN*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

*longitude = longitude1 / iPI;

*latitude = latitude1 / iPI;

}