ddt test 2 with .func

V1 1 0 dc 0 pulse 0 2 0 1 1 1 4

B2 2 0 v = ddt(V(1))

B3 3 0 v = border(v(1))

.func border(x) if (ddt(x) > 0, 1, 0)

.tran 1m 8

.control
run
plot v(1) v(2) v(3)
.endc

.end