# Size of variable arrays: sizeAlgebraic = 0 sizeStates = 0 sizeConstants = 18 from math import * from numpy import * def createLegends(): legend_states = [""] * sizeStates legend_rates = [""] * sizeStates legend_algebraic = [""] * sizeAlgebraic legend_voi = "" legend_constants = [""] * sizeConstants legend_constants[0] = "E11 in component interface (strain)" legend_constants[1] = "E22 in component interface (strain)" legend_constants[2] = "E33 in component interface (strain)" legend_constants[3] = "E12 in component interface (strain)" legend_constants[4] = "E13 in component interface (strain)" legend_constants[5] = "E23 in component interface (strain)" legend_constants[6] = "c1 in component interface (strain)" legend_constants[7] = "c2 in component interface (strain)" legend_constants[8] = "c3 in component interface (strain)" legend_constants[9] = "c4 in component interface (strain)" legend_constants[10] = "c5 in component interface (strain)" legend_constants[12] = "Tdev11 in component equations (stress)" legend_constants[13] = "Tdev22 in component equations (stress)" legend_constants[14] = "Tdev33 in component equations (stress)" legend_constants[15] = "Tdev12 in component equations (stress)" legend_constants[16] = "Tdev13 in component equations (stress)" legend_constants[17] = "Tdev23 in component equations (stress)" legend_constants[11] = "Q in component equations (strain)" return (legend_states, legend_algebraic, legend_voi, legend_constants) def initConsts(): constants = [0.0] * sizeConstants; states = [0.0] * sizeStates; constants[0] = 0 constants[1] = 0 constants[2] = 0 constants[3] = 0 constants[4] = 0 constants[5] = 0 constants[6] = 0.88 constants[7] = 0 constants[8] = 18.5 constants[9] = 3.58 constants[10] = 3.26 constants[11] = 2.00000*constants[7]*(constants[0]+constants[1]+constants[2])+constants[8]*(power(constants[0], 2.00000))+constants[9]*(power(constants[2], 2.00000)+power(constants[1], 2.00000)+(power(constants[5], 2.00000))*2.00000)+2.00000*constants[10]*(power(constants[4], 2.00000)+power(constants[3], 2.00000)) constants[12] = constants[6]*exp(constants[11])*(constants[7]+constants[8]*constants[0]) constants[13] = constants[6]*exp(constants[11])*(constants[7]+constants[9]*constants[1]) constants[14] = constants[6]*exp(constants[11])*(constants[7]+constants[9]*constants[2]) constants[15] = constants[6]*exp(constants[11])*constants[10]*constants[3] constants[16] = constants[6]*exp(constants[11])*constants[10]*constants[4] constants[17] = constants[6]*exp(constants[11])*constants[9]*constants[5] return (states, constants) def computeRates(voi, states, constants): rates = [0.0] * sizeStates; algebraic = [0.0] * sizeAlgebraic return(rates) def computeAlgebraic(constants, states, voi): algebraic = array([[0.0] * len(voi)] * sizeAlgebraic) states = array(states) voi = array(voi) 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)