# Size of variable arrays: sizeAlgebraic = 2 sizeStates = 2 sizeConstants = 12 from math import * from numpy import * def createLegends(): legend_states = [""] * sizeStates legend_rates = [""] * sizeStates legend_algebraic = [""] * sizeAlgebraic legend_voi = "" legend_constants = [""] * sizeConstants legend_voi = "time in component environment (second)" legend_states[0] = "a in component a (dimensionless)" legend_constants[7] = "alpha in component reaction_constants (dimensionless)" legend_constants[8] = "beta in component reaction_constants (dimensionless)" legend_algebraic[1] = "KP in component reaction_constants (dimensionless)" legend_states[1] = "g in component g (dimensionless)" legend_constants[9] = "gamma in component reaction_constants (dimensionless)" legend_constants[10] = "L in component reaction_constants (dimensionless)" legend_constants[0] = "k2 in component reaction_constants (dimensionless)" legend_constants[1] = "k3 in component reaction_constants (dimensionless)" legend_constants[2] = "k6 in component reaction_constants (dimensionless)" legend_constants[3] = "k7 in component reaction_constants (dimensionless)" legend_constants[4] = "k0 in component reaction_constants (dimensionless)" legend_constants[5] = "k4 in component reaction_constants (dimensionless)" legend_constants[6] = "km in component reaction_constants (dimensionless)" legend_constants[11] = "K in component reaction_constants (dimensionless)" legend_algebraic[0] = "P in component reaction_constants (dimensionless)" legend_rates[0] = "d/dt a in component a (dimensionless)" legend_rates[1] = "d/dt g in component g (dimensionless)" return (legend_states, legend_algebraic, legend_voi, legend_constants) def initConsts(): constants = [0.0] * sizeConstants; states = [0.0] * sizeStates; states[0] = 7.68E-8 states[1] = 3.43E-8 constants[0] = 6.0E-4 constants[1] = 0.0000048 constants[2] = 0.000891 constants[3] = 0.006831 constants[4] = 8.7831E-11 constants[5] = 2.1E12 constants[6] = 6.9001E-14 constants[7] = constants[1]/constants[0] constants[8] = constants[2]/constants[0] constants[9] = constants[3]/constants[0] constants[10] = power(((power(constants[6], 2.00000))*constants[5])/(power(constants[0], 3.00000)), 0.500000) constants[11] = power(((power(constants[4], 2.00000))*constants[5])/(power(constants[0], 3.00000)), 0.500000) return (states, constants) def computeRates(voi, states, constants): rates = [0.0] * sizeStates; algebraic = [0.0] * sizeAlgebraic rates[1] = ((1.00000-constants[7])*states[0]+states[0]*(power(states[1], 2.00000)))-(constants[10]+constants[9]*states[1]) algebraic[0] = 0.735000+0.156300*sin((2.00000*3.14159*voi)/(24.0000*3600.00))+0.312700*fabs(sin((3.14159*voi)/(24.0000*3600.00))) algebraic[1] = constants[11]*algebraic[0] rates[0] = algebraic[1]-((1.00000+constants[7]+constants[8])*states[0]+states[0]*(power(states[1], 2.00000))) return(rates) def computeAlgebraic(constants, states, voi): algebraic = array([[0.0] * len(voi)] * sizeAlgebraic) states = array(states) voi = array(voi) algebraic[0] = 0.735000+0.156300*sin((2.00000*3.14159*voi)/(24.0000*3600.00))+0.312700*fabs(sin((3.14159*voi)/(24.0000*3600.00))) algebraic[1] = constants[11]*algebraic[0] return algebraic def solve_model(): """Solve model with ODE solver""" from scipy.integrate import ode # Initialise constants and state variables (init_states, constants) = initConsts() # Set timespan to solve over voi = linspace(0, 10, 500) # Construct ODE object to solve r = ode(computeRates) r.set_integrator('vode', method='bdf', atol=1e-06, rtol=1e-06, max_step=1) r.set_initial_value(init_states, voi[0]) r.set_f_params(constants) # Solve model states = array([[0.0] * len(voi)] * sizeStates) states[:,0] = init_states for (i,t) in enumerate(voi[1:]): if r.successful(): r.integrate(t) states[:,i+1] = r.y else: break # Compute algebraic variables algebraic = computeAlgebraic(constants, states, voi) return (voi, states, algebraic) def plot_model(voi, states, algebraic): """Plot variables against variable of integration""" import pylab (legend_states, legend_algebraic, legend_voi, legend_constants) = createLegends() pylab.figure(1) pylab.plot(voi,vstack((states,algebraic)).T) pylab.xlabel(legend_voi) pylab.legend(legend_states + legend_algebraic, loc='best') pylab.show() if __name__ == "__main__": (voi, states, algebraic) = solve_model() plot_model(voi, states, algebraic)