% RC filter example
R = 330;
C = 47 * 10 ^ -6;
w = [ 10 : 0.1 : 10000 ];
z = lowpass (R, C, w);
s = 1/sqrt(2) .* ones (size (w));
loglog (w, z, w, s);
a = abs (z-s);
ma = min (a);
f = find ( a == ma);
f
w(f)
z(f)