Convert degrees, and minutes components into decimal degrees.
dms must be a 3 column matrix with one row per angle, and each column correspoding to its degrees (an integer), minutes (a less than 60 integer, and seconds (a less than 60 value, possibly fractional) components.
The sign of the angle must be defined on its first non-zero component only, i.e., if an angle is negative, the seconds component must be positive unless both minutes and degrees are zero, and the minutes component must be positive unless the degrees component is zero.
See also: degrees2dm, degree2dms, dm2degrees.
Package: mapping