Convert HK1980GRID coordinates to WGS84GEO coordinates

HK1980GRID_TO_WGS84GEO(N, E)

Arguments

N	Numeric, Northern coordinate in meters
E	Numeric, Eastern coordinate in meters

Details

This function converts the coordinates to HK80GEO first, and convert the later to WGS84GEO coordinates.

Value

latitude

latitude in decimal degrees

longitude

longitude in decimal degrees

References

Survey & Mapping Office Lands Department, Hong Kong Government (1995). Explanatory Notes on Geodetic Datums in Hong Kong, available at: http://www.geodetic.gov.hk/smo/gsi/data/pdf/explanatorynotes.pdf

Author

Jinlong Zhang

Note

The coordinates should be within the range of Hong Kong. Providing coordinates outside Hong Kong will lead to wrong results.

Examples

options(digits = 15)
HK1980GRID_TO_WGS84GEO(820351.389, 832591.320)
#>           latitude        longitude
#> 1 22.3221739419203 114.141179433862
#### $latitude
#### [1] 22.3221739419203
#### 
#### $longitude
#### [1] 114.141179433862

####  Answer from the online conversion tool
####  http://www.geodetic.gov.hk/smo/tform/tform.aspx
####  22.322172084   114.141187917