B,L,H==>X,Y,Z X,Y,Z==>B,L,H 大地问题正解 大地问题反解 3度带或6度带高斯投影正解, 3度带或6度带高斯投影反解,-B, L, H ==> X, Y, ZX, Y, Z ==> B, L, H Earth Positive Solution Solution 3 degrees counter-earth problems with or 6 degrees with Gauss projection positive so