def get_profile(R):
M = params.recipe['mass']
g = params.G * M / pow(R, 2.0)
P = params.recipe['P_surf']
T = None
phase = phases.get_phase(0, None, P, params.recipe['T_surf'])
rho = phase['rho_0']
q_surf = params.recipe['q_surf_est']
layersbelow_mass = params.recipe['mass']
radius = R
solution = [None] * 2
for layer_number in xrange(0, params.recipe['layers']):
x = np.linspace(0, radius, params.layerpoints)
layersbelow_mass = layersbelow_mass - params.recipe['layer_masses'][layer_number]
define_mass_event(layersbelow_mass)
layer_solution = odelay(structure_equations, [rho, g, M, P], x, events=[mass_event], args=(phase, radius, False))
# if(T is None): # uncomment this when you have T solved for and indent the next line
# If this is our first iteration we don't have an initial temperature profile yet
# create a constant profile of temperature T_surf.
# This means phase relations won't go insane in subsequent steps
T = np.zeros_like(layer_solution[0]) + params.recipe['T_surf']
solution[layer_number] = get_layer_properties(layer_solution, T, q_surf, layer_number, radius)
if (layer_number < params.recipe['layers'] - 1):
phase = phases.get_phase(layer_number + 1, None, P, 300)
radius = solution[layer_number]['bottom_r']
P = solution[layer_number]['bottom_P']
rho = phases.vinet_density(P, phase)
g = solution[layer_number]['bottom_g']
M = solution[layer_number]['bottom_m']
# Interp all my fields for use in the temperature ODE
solution = interp_solution(solution)
# Toss to the temperature solver
return solution
def ForceForwardToNextEvent(initialstate, eventType):
# take a small step forward (0.1 time units) so that the integration is sure to move forward from the current state
shorttimespan = np.linspace(0.0, 0.1, 10)
computeOneStep = integrate.odeint(nonlinearDerivativesFunction, initialstate, shorttimespan)
# this is the new initial state (last vector from short propagation above)
initialstate = computeOneStep[9]
# step to the next event (given maximum time constraint)
t, statesOverTime, EventTime, EventState, EventIndex = odelay(nonlinearDerivativesFunction, initialstate, timespan, events=[eventType, stop_maxTime])
EventTime = EventTime + 0.1;
return EventTime, EventState
def test_odelay_event():
X, Y, XE, YE, IE = odelay(ode, y0, xspan, events=[event], args=(k, ))
assert feq(XE[0], 0.3)
isterminal = False
return value, isterminal, direction
def maxima(y, x):
'''Approaching a maximum, dydx is positive and going to zero. our event function
is decreasing'''
value = ode(y, x)
direction = -1
isterminal = False
return value, isterminal, direction
xspan = np.linspace(0.0, 20.0, 100)
y0 = 0
X, Y, XE, YE, IE = odelay(ode, y0, xspan, events=[minima, maxima])
print(IE)
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
plt.plot(X, Y)
# blue is maximum, red is minimum
colors = 'rb'
for xe, ye, ie in zip(XE, YE, IE):
plt.plot([xe], [ye], 'o', color=colors[ie])
# plt.show()
from pycse import odelay
import numpy as np
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
def ode(y, x, k):
return -k * y
def event(y, x):
value = y - 0.3
isterminal = True
direction = 0
return value, isterminal, direction
xspan = np.linspace(0, 3)
y0 = 1
for k in [2, 3, 4]:
X, Y, XE, YE, IE = odelay(ode, y0, xspan, events=[event], args=(k, ))
plt.plot(X, Y)
# plt.show()
from pycse import odelay
import numpy as np
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
def ode(y, x, k):
return -k * y
def event(y, x):
value = y - 0.3
isterminal = True
direction = 0
return value, isterminal, direction
xspan = np.linspace(0, 3)
y0 = 1
for k in [2, 3, 4]:
X, Y, XE, YE, IE = odelay(ode, y0, xspan, events=[event], args=(k,))
plt.plot(X, Y)
# plt.show()
print(np.sum(y[0:-2] * y[1:-1] < 0))
# method two used ODE function to solve the derivative of initial functions
from pycse import odelay
# define functions
def fprime(f, x):
return 3.0 * x**2 + 12.0 * x - 4.0
def event(f, x):
value = f # we want f =0
isterminal = False
direction = 0
return value, isterminal, direction
xspan = np.linspace(-8, 4)
f0 = -120
X, F, TE, YE, IE = odelay(fprime, f0, xspan, events=[event])
for te, ye in zip(TE, YE):
print('root round at x ={0:1.3f},f={1:1.3f}'.format(te, float(ye)))
print('ODE done')
def test_odelay_minmax():
xspan = np.linspace(0.0, 20.0, 100)
y0 = 0
X, Y, XE, YE, IE = odelay(ode, y0, xspan, events=[minima, maxima])
assert (IE == [0, 1, 0, 1, 0, 1, 0]).all()
def test_odelay_minmax():
X, Y, XE, YE, IE = odelay(ode, y0, xspan, events=[minima, maxima])
assert (IE == [0, 1, 0, 1, 0, 1, 0]).all()
import matplotlib.pyplot as plt
Ca0 = 3.0 # mol / L
v0 = 10.0 # L / min
k = 0.23 # 1 / min
Fa_Exit = 0.3 * v0
def ode(Fa, V):
Ca = Fa / v0
return -k * Ca
def event1(Fa, V):
isterminal = False
direction = 0
value = Fa - Fa_Exit
return value, isterminal, direction
Vspan = np.linspace(0, 200) # L
V, F, TE, YE, IE = odelay(ode, Ca0 * v0, Vspan, events=[event1])
print('Solution is at {0} L'.format(V[-1]))
matplotlib.use('Agg')
plt.plot(V, F)
direction = 1
isterminal = False
return value, isterminal, direction
def maxima(y, x):
'''Approaching a maximum, dydx is positive and going to zero. our event function
is decreasing'''
value = ode(y, x)
direction = -1
isterminal = False
return value, isterminal, direction
xspan = np.linspace(0.0, 20.0, 100)
y0 = 0
X, Y, XE, YE, IE = odelay(ode, y0, xspan, events=[minima, maxima])
print(IE)
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
plt.plot(X, Y)
# blue is maximum, red is minimum
colors = 'rb'
for xe, ye, ie in zip(XE, YE, IE):
plt.plot([xe], [ye], 'o', color=colors[ie])
# plt.show()
y1, y2 = Y
value = y2 - (-1.0)
isterminal = True
direction = 0
return value, isterminal, direction
def event2(Y, x):
dy1dx, dy2dx = ode(Y,x)
value = dy1dx - 0.0
isterminal = False
direction = -1 # derivative is decreasing towards a maximum
return value, isterminal, direction
Y0 = [2.0, 1.0]
xspan = np.linspace(0, 5)
X, Y, XE, YE, IE = odelay(ode, Y0, xspan, events=[event1, event2])
plt.plot(X, Y)
for ie,xe,ye in zip(IE, XE, YE):
if ie == 1: #this is the second event
y1,y2 = ye
plt.plot(xe, y1, 'ro')
plt.legend(['$y_1$', '$y_2$'], loc='best')
#plt.savefig('images/odelay-mult-eq.png')
plt.show()
# <headingcell level=3>
# Example from pycse 2
def test_odelay_minmax():
xspan = np.linspace(0.0, 20.0, 100)
y0 = 0
X, Y, XE, YE, IE = odelay(ode, y0, xspan, events=[minima, maxima])
assert (IE == [0, 1, 0, 1, 0, 1, 0]).all()
def test_odelay_event():
X, Y, XE, YE, IE = odelay(ode, y0, xspan, events=[event], args=(k,))
assert feq(XE[0], 0.3)
# create a perturbed initial state
#initialstate2 = np.zeros(len(initialstate_H))
#initialstate2[0:3] = initialstate_H[0:3]
#initialstate2[3:6] = [x * 1.001 for x in initialstate_H[3:6]]
#print initialstate2
# <headingcell level=3>
# Define functions: ForceForwardToNextEvent, ForceForwardNEvents, FuncToSolve, Haloize
# <codecell>
''' from the pysce source code at https://github.com/jkitchin/pycse/blob/2c9ff7fe81b0dfb34b3edf87356817312910b799/pycse/PYCSE.py#L78
odelay(func, y0, xspan, events, fsolve_args=None, **kwargs):
ode wrapper with events func is callable, with signature func(Y, x)
y0 are the initial conditions xspan is what you want to integrate
over
events is a list of callable functions with signature event(Y, x).
These functions return zero when an event has happened.
[value, isterminal, direction] = event(Y, x)
value is the value of the event function. When value = 0, an event is triggered
isterminal = True if the integration is to terminate at a zero of
this event function, otherwise, False.
direction = 0 if all zeros are to be located (the default), +1
