cos-1.m

GNU Octave is a high-level language, primarily intended for numerical computations. It provides a c

rt2 = sqrt (2);
rt3 = sqrt (3);
x = [0, pi/6, pi/4, pi/3, pi/2, 2*pi/3, 3*pi/4, 5*pi/6, pi];
v = [1, rt3/2, rt2/2, 1/2, 0, -1/2, -rt2/2, -rt3/2, -1];
all (abs (cos (x) - v) < sqrt (eps))