Desinging a very basic 1st order integrator with the continous transfer function:
$H(s) = -1 / (0.001 s)$ [No zeros, one pole at origin]
I was expecting the unit step response to be positive-slope. However in my Python code I get a negative slope.
num = (0 , -1)
den = (0.001 , 0)
Hs = sig.lti(num,den)
t, s = sig.step(Hs)
plt.plot(t,s)
Provides: