angle
angle(X) returns the phase angle for each element of X (which is a matrix with complex values), expressed in radians.
Examples
> X = [1+i; -1+i] [X:2x1 double(complex)] > angle(X)# 0.785398163 2.35619449
> X = [1+i; -1+i] [X:2x1 double(complex)] > angle(X)# 0.785398163 2.35619449