HK1980GRID_TO_HK80GEO {HK80}

Convert HK1980GRID coordinates to HK80GEO coordinates

Description

Convert HK1980GRID coordinates to HK80GEO coordinates

Usage

HK1980GRID_TO_HK80GEO(N, E)

Arguments

N

Numeric, Northern coordinate in meters

E

Numeric, Eastern coordinate in meters

Details

This function uses equation 3, 4, 5 to convert the HK1980GRID coordinates into HK80GEO coordinates. More details could be found on the explanatory notes Page C9.

Value

latitude

latitude in decimal degrees

longitude

longitude in decimal degrees

Note

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

Author(s)

Jinlong Zhang

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

See Also

HK80GEO_TO_HK1980GRID

Examples

options(digits = 15)
HK1980GRID_TO_HK80GEO(820351.389, 832591.320)

### $latitude
### [1] 22.3237017196981
### 
### $longitude
### [1] 114.138734989417

#### The answer from the online conversion tool
### 22.323701767
### 114.138734989