This function converts between degrees, radians and gons. The
from and to arguments may be any of the follwoing
strings: "deg", "rad", "gon" and "str" for degrees, radians, gon
and streck respectivly. The output is not guaranteed to be within
the first turn, e.g. converting 10 radians yields almost 573
degrees as output.
Module reference for Pike v7.8 release 116, 2008-12-31