VC度分秒（时分秒）转换公式；求经纬度差；渐长纬度计算公式；已知两点经纬度求第二点相对第一点的方位距离,VC degrees minutes and seconds (time minute and second) conversion formula　seeking latitude and longitude difference　amidst growing latitude formula　2:00 longitude and latitude are known to seek the second orientation of the relative distance from the first point