#!/usr/bin/env python3

# -*- coding: utf-8 -*-

"""sisotooldemo.py

Shows some different systems with sisotool.

All should produce smooth root-locus plots, also zoomable and clickable,

with proper branching

"""

#%%

import matplotlib.pyplot as plt

import control as ct

# first example, aircraft attitude equation

s = ct.tf([1,0],[1])

Kq = -24

T2 = 1.4

damping = 2/(13**.5)

omega = 13**.5

H = (Kq*(1+T2*s))/(s*(s**2+2*damping*omega*s+omega**2))

plt.close('all')

ct.sisotool(-H)

#%%

# a simple RL, with multiple poles in the origin

plt.close('all')

H = (s+0.3)/(s**4 + 4*s**3 + 6.25*s**2)

ct.sisotool(H)

#%%

# a branching and emanating example

b0 = 0.2

b1 = 0.1

b2 = 0.5

a0 = 2.3

a1 = 6.3

a2 = 3.6

a3 = 1.0

plt.close('all')

H = (b0 + b1*s + b2*s**2) / (a0 + a1*s + a2*s**2 + a3*s**3)

ct.sisotool(H)