simulation.py
import numpy as np
import system_model
from scipy.integrate import solve_ivp
from ackrep_core import ResultContainer
from ackrep_core.system_model_management import save_plot_in_dir
import matplotlib.pyplot as plt
import os
# link to documentation with examples: https://ackrep-doc.readthedocs.io/en/latest/devdoc/contributing_data.html
def simulate():
"""
simulate the system model with scipy.integrate.solve_ivp
:return: result of solve_ivp, might contains input function
"""
model = system_model.Model()
rhs_xx_pp_symb = model.get_rhs_symbolic()
print("Computational Equations:\n")
for i, eq in enumerate(rhs_xx_pp_symb):
print(f"dot_x{i+1} =", eq)
rhs = model.get_rhs_func()
# ---------start of edit section--------------------------------------
# initial state values
xx0 = [0.9, 0.1]
t_end = 3
tt = np.linspace(0, t_end, 10000)
simulation_data = solve_ivp(rhs, (0, t_end), xx0, t_eval=tt)
# ---------end of edit section----------------------------------------
save_plot(simulation_data)
return simulation_data
def save_plot(simulation_data):
"""
plot your data and save the plot
access to data via: simulation_data.t array of time values
simulation_data.y array of data components
simulation_data.uu array of input values
:param simulation_data: simulation_data of system_model
:return: None
"""
# ---------start of edit section--------------------------------------
# plot of your data
plt.plot(simulation_data.t, simulation_data.y[0], label="x")
plt.plot(simulation_data.t, simulation_data.y[1], label="y")
plt.xlabel("Time [s]")
plt.grid()
plt.legend()
# ---------end of edit section----------------------------------------
plt.tight_layout()
save_plot_in_dir()
def evaluate_simulation(simulation_data):
"""
assert that the simulation results are as expected
:param simulation_data: simulation_data of system_model
:return:
"""
# ---------start of edit section--------------------------------------
# fill in final states of simulation to check your model
# simulation_data.y[i][-1]
expected_final_state = [-1.97853335, -2.2095157]
# ---------end of edit section----------------------------------------
rc = ResultContainer(score=1.0)
simulated_final_state = simulation_data.y[:, -1]
rc.final_state_errors = [
simulated_final_state[i] - expected_final_state[i] for i in np.arange(0, len(simulated_final_state))
]
rc.success = np.allclose(expected_final_state, simulated_final_state, rtol=0, atol=1e-2)
return rc
system_model.py
import sympy as sp
import symbtools as st
import importlib
import sys, os
# from ipydex import IPS, activate_ips_on_exception
from ackrep_core.system_model_management import GenericModel, import_parameters
# Import parameter_file
params = None
# link to documentation with examples: https://ackrep-doc.readthedocs.io/en/latest/devdoc/contributing_data.html
class Model(GenericModel):
def initialize(self):
"""
this function is called by the constructor of GenericModel
:return: None
"""
# ---------start of edit section--------------------------------------
# Define number of inputs -- MODEL DEPENDENT
self.u_dim = 0
# Set "sys_dim" to constant value, if system dimension is constant
self.sys_dim = 2
# ---------end of edit section----------------------------------------
# check existence of params file
self.has_params = False
self.params = params
# ----------- SYMBOLIC RHS FUNCTION ---------- #
def get_rhs_symbolic(self):
"""
define symbolic rhs function
:return: matrix of symbolic rhs-functions
"""
if self.dxx_dt_symb is not None:
return self.dxx_dt_symb
# ---------start of edit section--------------------------------------
x1, x2 = self.xx_symb # state components
# define symbolic rhs functions
dx1_dt = 2 * x2
dx2_dt = (x1 + x2) * (-((x1 - x2) ** 2) + 1)
# rhs functions matrix
self.dxx_dt_symb = sp.Matrix([dx1_dt, dx2_dt])
# ---------end of edit section----------------------------------------
return self.dxx_dt_symb
parameters.py
# This model does not need any parameters.