EPSG
EPSG guidance note #7.
2002-11-22
Applies to 2D and the horizontal component of 3D ellipsoidal systems.
In the formulas that follow, the coordinate strings are symbolically represented as follows: deg decimal degrees adeg absolute value of decimal degrees ideg integer degrees sdeg signed integer degree min real-number minutes imin integer minutes sec real-number seconds lathem, lonhem hemisphere abbreviation The degree and hemisphere parameters remain unchanged in this conversion (both forward and reverse) and also retain their position in their respective coordinate strings. Forward calculation from DMH representation to DMSH representation: imin = INT(min) sec = (min - imin) * 60 Reverse calculation from DMSH representation to DMH representation: min = imin + (sec / 60)