[FIDOCAD]
RV 55 50 25 25 0
RV 85 25 115 50 0
LI 55 35 85 35 0
FCJ 2 0 3 2 0 0
LI 115 35 140 35 0
FCJ 2 0 3 2 0 0
LI 5 35 25 35 0
FCJ 2 0 3 2 0 0
TY 33 33 4 3 0 0 0 * w=y^2
TY 95 35 4 3 0 0 0 * H(f)
TY 124 28 4 3 0 0 0 * z(t)
TY 63 28 4 3 0 0 0 * w(t)
TY 10 27 4 3 0 0 0 * y(t)