Exemple #1
0
def restricted_3body(y):  # y = [r, v] expected
    testbody = set_scene(y[0])
    t, h = 0.0, 0.001
    while True:
        vp.rate(2000)
        y = ode.RK4(r3body, y, t, h)
        testbody.pos = y[0]
Exemple #2
0
def go(vx=5., vy=5.):  # default velocity=(5,5)
    Y = [0., 0., vx, vy]  # initial values, [x,y,vx,vy]
    t, h, x, y = 0., .01, [], []  # time, step size, temp arrays
    while Y[1] >= 0.0:  # loop as long as y>=0
        x.append(Y[0]), y.append(Y[1])  # record pos.
        Y, t = ode.RK4(Lin_drag, Y, t, h), t + h  # update Y, t

    plt.figure()  # open fig, plot, label, show fig
    plt.plot(x, y), plt.xlabel('x (m)'), plt.ylabel('y (m)')
    plt.show()
def go(x, y, vx, vy):  # motion with full drag and spin effects
    h, t, Y = 0.01, 0., np.array([[x, y, 0.], [vx, vy, 0.]])  # initialize
    while (Y[0, 0] < R and Y[0, 1] > 0.2):  # before homeplate&above ground
        vp.rate(40)
        t, Y = t + h, ode.RK4(baseball, Y, t, h)  # integrate
        ball.pos, spin.pos = Y[0], Y[0] - offset  # move ball, arrow
        spin.rotate(angle=phi), ball.rotate(angle=phi, axis=omega)  #spin
        trail.append(pos=ball.pos)
        ideal.append(pos=(x + vx * t, y + vy * t - 0.5 * g * t * t,
                          0.))  # ideal case
    while (not scene.kb.keys):  # check for key press
        vp.rate(40)
        spin.rotate(angle=phi), ball.rotate(angle=phi, axis=omega)
    scene.kb.getkey()  # clear key
    trail.append(pos=(0, 0, 0), retain=0)  # reset trails
    ideal.append(pos=(0, 0, 0), retain=0)
import ode

initial_nuclei = 10000.0
decay_constant = 0.2

def decay(t, y):
    return -decay_constant * y[0]

print('Solving using Euler method......')
for i in [x for x in ode.Euler([decay], 0.0, [initial_nuclei], 0.1, 50.0)]:
    print(','.join([str(x) for x in i]))
print('')

print('Solving using RK4 method......')
for i in [x for x in ode.RK4([decay], 0.0, [initial_nuclei], 0.1, 50.0)]:
    print(','.join([str(x) for x in i]))
print('')

print('Solving using RK3 method......') 
for i in [x for x in ode.RK3([decay], 0.0, [initial_nuclei], 0.1, 50.0)]:
    print(','.join([str(x) for x in i]))
print('')

print("Solving using Heun's method......")
for i in [x for x in ode.Heun([decay], 0.0, [initial_nuclei], 0.1, 50.0)]:
    print(','.join([str(x) for x in i]))
print('')

print('Solving using RK4 method with 3/8 rule......')
for i in [x for x in ode.RK38([decay], 0.0, [initial_nuclei], 0.1, 50.0)]:
Exemple #5
0
    resurrected = resurect * y[2]
    destroyed = destroy * y[0] * y[1]
    return newly_infected + resurrected - destroyed


def dead(t, y):
    natural_death = death * y[0]
    destroyed_zombies = destroy * y[0] * y[1]
    created_zombies = resurect * y[2]
    return natural_death + destroyed_zombies - created_zombies


def modifying_expression(y, step):
    y[0] = y[0] + (5 * step)
    return y


lower_bound = {'2': [0.0, 0.0]}
upper_bound = {'0': [700, 700]}

f = [human, zombie, dead]  # system of ODEs

y = [500.0, 0, 0]  # initial human, zombie, death population respectively
print('Solving using 4th order Runge Kutta method ......')
for i in [
        x for x in ode.RK4(f, 0.0, y, 0.1, 100.0, modifying_expression,
                           lower_bound, upper_bound)
]:
    print(','.join([str(z) for z in i]))
print('')
    f[1:, :] -= ftop  # below, left: use 3rd law
    f[:, 1:] -= fright
    a = (f - damp * v) / mass + gvec
    v[0, 0], v[0, -1], v[-1, 0], v[-1, -1] = 0, 0, 0, 0  # fixed coners
    return np.array([v, a])


L, M, N = 2.0, 15, 15  # size, (M,N) particle array
h, mass, damp = 0.01, 0.004, 0.01  # keep damp between [.01,.1]
x, y = np.linspace(0, L, M), np.linspace(0, L, N)  # particle grid
r, v = np.zeros((N, M, 3)), np.zeros((N, M, 3))
spring_k, spring_l = 50.0, x[1] - x[0]  # spring const., relaxed length
r[:, :, 0], r[:, :, 1] = np.meshgrid(x, y)  # initialize pos
Y, gvec = np.array([r, v]), np.array([0, 0, -9.8])  # [v,a], g vector

scene = vp.display(title='Tablecloth',
                   background=(.2, .5, 1),
                   up=(0, 0, 1),
                   center=(L / 2, L / 2, -L / 4),
                   forward=(1, 2, -1))
vp.points(pos=[(0, 0, 0), (0, L, 0), (L, L, 0), (L, 0, 0)], size=50)  # corners
x, y, z = r[:, :, 0], r[:, :, 1], r[:, :, 2]  # mesh points
net = vpm.net(x, y, z, vp.color.yellow, 0.005)  # mesh net
mesh = vpm.mesh(x, y, z, vp.color.red, vp.color.yellow)

while (1):
    vp.rate(100), vpm.wait(scene)  # pause if key pressed
    Y = ode.RK4(cloth, Y, 0, h)
    x, y, z = Y[0, :, :, 0], Y[0, :, :, 1], Y[0, :, :, 2]
    net.move(x, y, z), mesh.move(x, y, z)
def CustomModel(CustomName, IntInput, InfRateInput, RecoveryInput, TimeInput):
    #Custom Model
    global r_RI, r_SI
    Name = CustomName
    print()
    PopInput = int(input("Enter an amount for the total population: "))
    print()
    SusInput = int(
        input("Enter an amount for the initial susceptible population: "))
    print()
    InfInput = int(
        input("Enter an amount for the initial infected population: "))
    print()
    print(
        "As of right now, this custom model does not support any carrier modifications. Maybe that will change in the future when a more advanced version of this code is created..."
    )
    print()

    #Initial Population Counts
    TotalPop = PopInput  #Total Population
    SusPop = SusInput  #Initial Susceptible Population
    InfPop = InfInput  #Initial Infected Population
    TotalInteractions = IntInput  #number of daily interactions an infected person has with the total population
    SusceptibleInteractions = InfRateInput  #how many interactions between an infected and susceptible people it takes to result in infection
    RI = 1 / RecoveryInput  #Recovery Rate (1/length of time it takes a person to recover)
    Time = TimeInput  #Time, in days, the disease is being modelled over

    #Time Setup
    t = 0  #initial time
    dt = 0.01  #change in time

    #Redefining Variables for S-I-R Formula
    N = TotalPop  #total population
    S = SusPop  #initial amount of susceptible people
    I = InfPop  #initial amount of infected people
    R = 0  #initial amount of recovered people
    f = TotalInteractions  #number of daily interactions an infected person has with the total population
    Ptrans = 1 / SusceptibleInteractions  #fraction of interactions between an infected person and a susceptible person that results in spread
    r_SI = (
        (f * Ptrans) / N
    )  #transmission rate, how likely it is for an infected person to spread the disease
    r_RI = RI  #recovery rate, time it takes for a person to recover

    #Creating lists for each variable in SIR formula
    tmodel = []
    Smodel = []
    Imodel = []
    Rmodel = []
    data = np.array([S, I, R])

    #Loop to actually run the Euler/RK method differential equations
    while t < Time:

        #Selecting which model to use
        #data=ode.Euler(rates,data,t,dt) #Uses Euler Model
        #data=ode.RK2(rates,data,t,dt)   #Uses Runge-Kutta 2 Model
        data = ode.RK4(rates, data, t, dt)  #Uses Runge-Kutta 4 Model

        #Advancing time
        t = t + dt

        #Appending each variable list
        tmodel.append(t)
        Smodel.append(data[0])
        Imodel.append(data[1])
        Rmodel.append(data[2])

    #Plotting Data
    fig = plt.figure(figsize=(10, 6))
    plt.title("SIR Model of Disease Spread for " + str(Name))
    plt.xlabel("Time (days)")
    plt.ylabel("Population")
    plt.plot(tmodel, Smodel, 'b-', label='Susceptible Population')
    plt.plot(tmodel, Imodel, 'r-', label='Infected Population')
    plt.plot(tmodel, Rmodel, 'g-', label='Recovered Population')
    plt.legend(loc="best")
    plt.grid()
    plt.show()
def ViDmModel(CarrierInput, IntInput, InfRateInput, RecoveryInput, TimeInput):
    #Model for Aldridge Village Dormatory
    global r_RI, r_SI
    Name = "Aldridge Village Dormatory"
    Shorthand = "Village"
    TotalPop = 250  #Total Population
    SusPop = 249  #Initial Susceptible Population
    InfPop = 1  #Initial Infected Population
    TotalInteractions = IntInput  #number of daily interactions an infected person has with the total population
    SusceptibleInteractions = InfRateInput  #how many interactions between an infected and susceptible people it takes to result in infection
    RI = 1 / RecoveryInput  #Recovery Rate (1/length of time it takes a person to recover)
    Time = TimeInput  #Time, in days, the disease is being modelled over

    #Carrier Stuff
    #List of Potential Carriers of the Disease and how they Impact the Spread
    Carrier = float(CarrierInput)
    BirdMod = 0.2
    RodentMod = 0.4
    InsectMod = 0.6
    BloodMod = 0.5
    SalivaMod = 0.2
    TouchMod = 0.7
    AirMod = 0.3
    WaterMod = 0.4
    NoMod = 0.0

    #If-statements determine which Carrier is in use and assigns the proper impact on the spread
    if Carrier == 1:
        CarrierMod = BirdMod
    if Carrier == 2:
        CarrierMod = RodentMod
    if Carrier == 3:
        CarrierMod = InsectMod
    if Carrier == 4:
        CarrierMod = BloodMod
    if Carrier == 5:
        CarrierMod = SalivaMod
    if Carrier == 6:
        CarrierMod = TouchMod
    if Carrier == 7:
        CarrierMod = AirMod
    if Carrier == 8:
        CarrierMod = WaterMod
    if Carrier == 9:
        CarrierMod = NoMod

    #Assigns the impact a carrier as on the spread, as well as determines how much, as a percentage, the carrier increased the spread
    CarrierImpact = CarrierMod

    #Time Setup
    t = 0  #initial time
    dt = 0.01  #change in time

    #Redefining Variables for S-I-R Formula
    N = TotalPop  #total population
    S = SusPop  #initial amount of susceptible people
    I = InfPop  #initial amount of infected people
    R = 0  #initial amount of recovered people
    f = TotalInteractions  #number of daily interactions an infected person has with the total population
    Ptrans = 1 / SusceptibleInteractions  #fraction of interactions between an infected person and a susceptible person that results in spread
    r_SI = (
        (f * Ptrans) / N
    ) * CarrierImpact  #transmission rate, how likely it is for an infected person to spread the disease
    r_RI = RI  #recovery rate, time it takes for a person to recover

    #Creating lists for each variable in SIR formula
    tmodel = []
    Smodel = []
    Imodel = []
    Rmodel = []
    data = np.array([S, I, R])

    #Loop to actually run the Euler/RK method differential equations
    while t < Time:

        #Selecting which model to use
        #data=ode.Euler(rates,data,t,dt) #Uses Euler Model
        #data=ode.RK2(rates,data,t,dt)   #Uses Runge-Kutta 2 Model
        data = ode.RK4(rates, data, t, dt)  #Uses Runge-Kutta 4 Model

        #Advancing time
        t = t + dt

        #Appending each variable list
        tmodel.append(t)
        Smodel.append(data[0])
        Imodel.append(data[1])
        Rmodel.append(data[2])

    #Plotting Data
    fig = plt.figure(figsize=(10, 6))
    plt.title(
        "SIR Model of a Disease across Different Buildings on HPU's Campus: " +
        str(Shorthand))
    plt.xlabel("Time (days)")
    plt.ylabel("Population")
    plt.plot(tmodel, Smodel, 'b-', label='Susceptible Population')
    plt.plot(tmodel, Imodel, 'r-', label='Infected Population')
    plt.plot(tmodel, Rmodel, 'g-', label='Recovered Population')
    plt.legend(loc="best")
    plt.grid()
    plt.show()