std-dtr, std-rtd | ![]() |
(std-dtr <degree>) ; "Degree to radians"
(std-rtd <radians>) ; "Radians to degree"
std-dtr converts an angle in degree notation to radians.
std-rtd converts an angle in radian notation to degrees.
Degrees are counted from 0 to 360 and radians from 0 to 2*PI.
The range of the result is not limited to the range 0 - 2*PI resp 0 to 360. It may be negative or greater, dependent on the range of the argument.
std-dtr is a convenient way to read and write angles in code which requires radians.
std-dtr may be used, besides angtos, to convert results in radians to degrees
(std-dtr 90) => (std-rtd *PI2*) => 360.0
radians: a real number
degree: a real number
A real number
None
(std-require 'STDMATH)
Defined in STDMATH