**ANGLE, ANGLEDEG, and ANGLERAD**

Angle(X), AngleDeg(X) and AngleRad(X) all return the angle (also called amplitude or argument) of complex variable X. Representing X as X_r + i*X_i, this function returns arctan(X_i/X_r). The difference between these three functions is the units in which the angle is returned.

Angle will return the angle in either degrees or radians depending on the Trig Function setting in the Unit System dialog.

AngleDeg will always return the angle in degrees.

AngleRad will always return the angle in radians.

All three functions return the angle in the correct quadrant of complex plane.

Examples: Y=Angle(X); YD=AngleDeg(X); YR=AngleRad(X)

The first example will set the real part of Y (Y_r) to the angle of X and the imaginary part of Y to zero.

Note that the Angle functions are used to extract the angle of a complex number variable or expression. They cannot be used for assigning the angle of a complex number. For example, the equation Angle(X)=4 will produce an error.

See also: Magnitude, CIS, Complex Numbers, Mathematical Functions