26.13.4  Measure of an angle in the plane

See Section 27.10.9 for angle measures in 3D geometry.

The angle command finds the measure of an angle.

• angle takes three mandatory arguments and one optional argument:
  • A,B,C, three points.
  • str, a string.
• angle(A,B,C ⟨,str ⟩) returns the measure of angle ABC (in the units that Xcas is configured for). With the argument str, the angle will be drawn indicated by a small arc and labeled with the string. If the angle is a right angle, the indicator will be a corner rather than an arc.

Examples

The angle command has angleat and angleatraw versions (see Section 26.13.1). For the command line versions of these commands, the optional fourth argument for angle is replaced by a mandatory fourth argument for the point to put the measurement.

Converting between radians and degrees.

You can use radians and degrees commands to convert from degrees to radians and vice versa, respectively. These commands return inexact values.