Unable to Get For Loop to Work in Python Script - python

Good Afternoon,
I am trying to use a for loop to plot graphics via basemap/matplotlib using 10 different data files. Using the code below, it only outputs the plot from the 9th time step/file.
Code:
tau = 0
for tau in range(0,10):
d_num = "d" + str(tau)
day = "day" + str(tau)
date = datetime.now() + timedelta(days=(tau))
custom_date = date.strftime('%a %d-%b-%y')
image_date = date.strftime('%Y%m%d')
homedir='/home/weather/'
domain='ne'
def mapformat():
m = Basemap(llcrnrlon=-85,llcrnrlat=36.5,urcrnrlon=-64,urcrnrlat=47,
projection='lcc',lat_1=33,lat_2=45,lon_0=-70,lon_1=-60, resolution='i')
m.drawmapboundary(fill_color='aqua', zorder=-1)
return m
data = np.loadtxt('/home/weather/data/' + d_num + '_tmaxs', delimiter=',', skiprows=1)
m = mapformat()
dx = 0.25
grid_x, grid_y = np.mgrid[-85:-60:dx, 34:50:dx] #Northeast
temp = data[:,0]
grid_z = griddata((data[:,2],data[:,1]), data[:,0], (grid_x,grid_y), method='cubic')
x,y = m(data[:,2], data[:,1]) # flip lat/lon
grid_x,grid_y = m(grid_x,grid_y)
m.contour(grid_x,grid_y,grid_z,clevs2,cmap=custom,linewidths=0.5,zorder=1)
cbar.set_label('Fahrenheit')
plt.savefig(homedir + "/out/abc_tmax_" + d_num + "_ne.png", dpi = 300)
sys.exit()

Related

Python function calling with variable vs raw numbers

I am trying to implement a pso algorithm from Wikipedia https://en.wikipedia.org/wiki/Particle_swarm_optimization.
My problem is that when I am calling the cost function with a variable (Gbest), and then manually calling the cost function (with the Gbest data) I get a different output (cost) like the image bellow:
Code fault
I am new to python so thank you for any suggestions.
Here is the complete code:
import matplotlib.pyplot as plt
import numpy as np
from control.matlab import *
A = np.array([[0,0,1],[0,1,0],[1,2,-2]])
B = np.array( [[0],[1],[0]])
C = np.array([[0, 1,0]])
D = np.zeros([C.shape[0],B.shape[1]])
sys = ss(A,B,C,D)
sys_tf = tf(sys)
s = tf('s')
def cost(kp,ki):
global sys_tf, G, y, t, r
G = kp + ki/s
C = feedback(sys_tf*G, 1)
y, t = step(C, linspace(0,100))
r = np.ones(len(t))
return np.sum(y-r)**2
part = 100
ite = 10000
dim = 2
w = 0.001
wdamp = 0.99
phip = 0.9
phig = 0.1
blo, bup = -10,10
x = np.zeros([dim, part])
v = np.zeros([dim, part])
pbest = np.zeros([dim, part])
gbest = np.array([1000000,1000000])
for i in range(part):
for k in range(dim):
x[k][i] = pbest[k][i] = np.random.uniform(blo, bup)
v[k][i] = np.random.uniform(-np.abs(bup - blo), np.abs(bup - blo))
if cost(pbest[0][i], pbest[1][i]) < cost(gbest[0], gbest[1]):
gbest = np.array([pbest[0][i], pbest[1][i]])
for it in range(ite):
for i in range(part):
for k in range(dim):
rp = np.random.uniform(0,1)
rg = np.random.uniform(0,1)
v[k,:] = w*v[k,:] + phip*rp*(pbest[k,:] - x[k,:]) + phig*rg*(gbest[k] - x[k,:])
x[k,:] = x[k,:] + v[k,:]
w = w*wdamp
if cost(x[0][i], x[1][i]) < cost(pbest[0][i], pbest[1][i]):
pbest[:,i] = x[:,i]
if cost(pbest[0][i], pbest[1][i]) < cost(gbest[0], gbest[1]):
gbest = np.array([pbest[0][i], pbest[1][i]])
plt.plot(t, y, 'ro')
plt.plot(t, r, 'x')
plt.pause(0.005)
plt.title(gbest)
print([gbest, cost(gbest[0], gbest[1])])

System of seven ODEs solve using solve_ivp or implement RK4

I'm trying solve a system of coupled ordinary differential equations, formed by 7 ODEs in python, using solve_ivp or either implement a fuction for RK4.
The general physical problem is as follows:
Cooling of photovoltaic modules with heat exchanger coupling to the module. In this way, the module generates electrical energy and thermal energy.
I have a polynomial function, G(t) = 9.8385e-13*t^4 - 1.82918e-8*t^3 + 5.991355e-05*t^2 + 2.312059e-1*t + 25, which works for an approximate range of 0 < t < 9000, which represents solar radiation as a function of time of day.
This function was obtained through a "polyfit" applied to real data (file upload here. Its a CSV - https://files.fm/u/9y4evkf6c).
This function is used as input for the ODEs, which represent an electrical and a thermal system as a function of time.
To solve the electrical model, I created some scripts that solve the diode equation for the photovoltaic module in question, and the output of this script is the photovoltaic power (called in the PPV thermal model) generated as a function of the module temperature and radiation. This script works great and solves part of my problem.
My difficulty lies in solving the equations of the thermal model, which receives as input parameters G(t) and PPV.
The equations result in this system:
System of EDOS
Labels:
Tvidro = Tglass = T1
Tcel = Tpv = T2
Ttedlar = T3
Tabs = Tabsorber = T4
Ttubo = Ttube = T5
Tfsai = Tfluid_out = T6
Tiso = Tinsulation = T7
Using method/function for RK4, the complete code is like this (you can go direct to part "#DEFINE MODEL EQUATIONS - ODES)" :
import numpy as np
import matplotlib.pyplot as plt
import csv
from numpy.polynomial.polynomial import polyval
############################################################
with open('directory of data called teste_dados_radiacao',"r") as i:
rawdata = list(csv.reader(i, delimiter = ";"))
exampledata = np.array(rawdata[1:], dtype=float)
xdata = exampledata[:,0]
ydata = exampledata[:,1]
curve = np.array(np.polyfit(xdata, ydata, 4))
rev_curve = np.array(list(reversed(curve)), dtype=float)
print(rev_curve)
#G_ajustado = polyval(xdata, rev_curve)
""" plt.plot(xdata, ydata, label = "dados experimentais")
plt.plot(xdata, model, label = "model")
plt.legend()
plt.show() """
#############################################################
#CONSTANTS
Tamb = 25 #°C #ambient temperatura
SIGMA = 5.67e-8 #W/m2K4
E_VIDRO = 0.90 #between 0.85 e 0.83 #nasrin2017 0.04
VENTO = 2 #m/s
T_GROUND = Tamb + 2 #°C
T_CEU = 0.00552*Tamb**1.5
Vf = 1 #m/s
Do = 10e-3 #m
Di = 8e-3 #m
NS = 6*10 #number of cells
T_F_ENT = 20 #°C
#INPUTS
Tcel = 25
Tv = 25
Tiso = 30
Av = 1.638*0.982
ALPHA_VIDRO = 0.9
L_VIDRO = 3e-3 #m
RHO_VIDRO = 2500 #kg/m3
M_VIDRO = Av*L_VIDRO*RHO_VIDRO #kg
CP_VIDRO = 500 #j/kgK
K_VIDRO = 2 #W/mK
TAU_VIDRO = 0.95
Pac = 0.85
H_CELL = 0.156 #m
A_CELL = NS*H_CELL**2
ALPHA_CELL = 0.9
L_CEL = 3e-3
RHO_CEL = 2330
M_CEL = A_CELL*L_CEL*RHO_CEL #kg - estimated
CP_CEL = 900 #J/kgK
K_CEL = 140 #W/mK
BETA_T = 0.43/100 # %/°C
N_ELE_REF = 0.1368 #13.68%
N_ELE = N_ELE_REF*(1 - BETA_T*(Tcel - 25)) #273 + 25 - tcel kelvin
A_tedlar = Av
L_TEDLAR = 0.33e-3
RHO_TEDLAR = 1500
M_TEDLAR = Av*L_TEDLAR*RHO_TEDLAR
CP_TEDLAR = 1090 #1090 OU 2090
K_TEDLAR = 0.35
ALPHA_TEDLAR = 0.34 #doc nasa ou zero
#parameters
RHO_ABS = 2700
A_ABS = Av
CP_ABS =900
L_ABS = 3e-3 #mm
M_ABS = A_ABS*RHO_ABS*L_ABS
K_ABS = 300
A_ABS_TUBO = 10*1.60*0.01+0.154*9*0.01
A_ABS_ISO = Av-A_ABS_TUBO
RHO_TUBO = 2700
CP_TUBO = 900
N_TUBOS = 10
L_TUBO = N_TUBOS*1.6
M_TUBO = RHO_TUBO*L_TUBO*(3.1415/4)*(Do**2 - Di**2)
K_TUBO = 300
A_TUBO_F = 0.387 #pi*Di*(L*10 VOLTAS + R(156MM)*9)
A_TUBO_ISO = 0.484 #pi*Do*(L*10 VOLTAS + R(156MM)*9)
A_ISO = Av
RHO_ISO = 50
L_ISO = 40e-3
M_ISO = A_ISO*RHO_ISO*L_ISO
CP_ISO = 670
K_ISO = 0.0375
E_ISO = 0.75 #ESTIMATED
RHO_FLUIDO = 997
M_FLUIDO = L_TUBO*(3.1415/4)*Di**2*RHO_FLUIDO
CP_FLUIDO = 4186 #j/kgK
MI_FLUIDO = 0.890e-3 #Pa*s ou N/m2 * s
K_FLUIDO = 0.607
M_PONTO = 0.05 #kg/s ou 0.5 kg/m3
#DIMENSIONLESS
Pr = CP_FLUIDO*MI_FLUIDO/K_FLUIDO #water 25°C
Re = RHO_FLUIDO*Vf*Di/MI_FLUIDO
if (Re<=2300):
Nuf = 4.364
else:
Nuf = 0.023*(Re**0.8)*(Pr*0.4)*Re
#COEFFICIENTS
h_rad_vidro_ceu = SIGMA*E_VIDRO*(Tv**2 - T_CEU)*(Tv + T_CEU)
h_conv_vidro_amb = 2.8 + 3*VENTO
h_conv_tubo_fluido = 0.5*30#Nuf
h_cond_vidro_cel = 1/((L_VIDRO/K_VIDRO) + (L_CEL/K_CEL))
h_cond_cel_tedlar = 1/((L_TEDLAR/K_TEDLAR) + (L_CEL/K_CEL))
h_cond_tedlar_abs = 1/((L_TEDLAR/K_TEDLAR) + (L_ABS/K_ABS))
h_cond_abs_tubo = 1/((L_TUBO/K_TUBO) + (L_ABS/K_ABS))
h_cond_abs_iso = 1/((L_ISO/K_ISO) + (L_ABS/K_ABS))
h_cond_tubo_iso = 1/((L_ISO/K_ISO) + (L_TUBO/K_TUBO))
h_conv_iso_amb = h_conv_vidro_amb
h_rad_iso_ground = SIGMA*E_ISO*(Tiso**2 - T_GROUND**2)*(Tiso + T_GROUND)
#GROUPS
A1 = (1/(M_VIDRO*CP_VIDRO))*(ALPHA_VIDRO*Av)#*G(t)) G_ajustado = polyval(dt,rev_curve)
A2 = (1/(M_VIDRO*CP_VIDRO))*(Av*(h_rad_vidro_ceu + h_conv_vidro_amb + h_cond_vidro_cel))
A3 = (1/(M_VIDRO*CP_VIDRO))*Av*h_cond_vidro_cel
A4 = (1/(M_VIDRO*CP_VIDRO))*Av*(h_conv_vidro_amb + h_rad_vidro_ceu)
A5 = (1/(M_CEL*CP_CEL))*(Pac*A_CELL*TAU_VIDRO*ALPHA_CELL) #*G(t)
A6 = -1*A5*N_ELE #*G(t)
A7 = (1/(M_CEL*CP_CEL))*A_CELL*h_cond_vidro_cel
A8 = (1/(M_CEL*CP_CEL))*A_CELL*(h_cond_vidro_cel + h_cond_cel_tedlar)
A9 = (1/(M_CEL*CP_CEL))*A_CELL*h_cond_cel_tedlar
A10 = (1/(M_TEDLAR*CP_TEDLAR))*A_tedlar*(1 - Pac)*TAU_VIDRO*ALPHA_TEDLAR#G(t)
A11 = (1/(M_TEDLAR*CP_TEDLAR))*A_tedlar*(h_cond_cel_tedlar + h_cond_tedlar_abs)
A12 = (1/(M_TEDLAR*CP_TEDLAR))*A_tedlar*h_cond_cel_tedlar
A13 = (1/(M_TEDLAR*CP_TEDLAR))*A_tedlar*h_cond_tedlar_abs
A14 = (1/(M_ABS*CP_ABS))*A_ABS*h_cond_tedlar_abs
A15 = (1/(M_ABS*CP_ABS))*(A_ABS*h_cond_tedlar_abs + A_ABS_TUBO*h_cond_abs_tubo + A_ABS_ISO*h_cond_abs_iso)
A16 = (1/(M_ABS*CP_ABS))*A_ABS_TUBO*h_cond_abs_tubo
A17 = (1/(M_ABS*CP_ABS))*A_ABS_ISO*h_cond_abs_iso
A18 = (1/(M_TUBO*CP_TUBO))*A_ABS_TUBO*h_cond_abs_tubo
A19 = (1/(M_TUBO*CP_TUBO))*(A_ABS_TUBO*h_cond_abs_tubo + A_TUBO_F*h_conv_tubo_fluido + A_TUBO_ISO*h_cond_tubo_iso)
A20 = (1/(M_TUBO*CP_TUBO))*A_TUBO_F*h_conv_tubo_fluido*0.5
A21 = (1/(M_TUBO*CP_TUBO))*A_TUBO_ISO*h_cond_tubo_iso
A22 = (1/(M_FLUIDO*CP_FLUIDO))*A_TUBO_F*h_conv_tubo_fluido
A23 = (1/(M_FLUIDO*CP_FLUIDO))*(A_TUBO_F*h_conv_tubo_fluido*0.5 + M_PONTO*CP_FLUIDO)
A24 = (1/(M_FLUIDO*CP_FLUIDO))*(T_F_ENT*(M_PONTO*CP_FLUIDO - h_conv_tubo_fluido*A_TUBO_F*0.5))
A25 = (1/(M_ISO*CP_ISO))*A_ABS_ISO*h_cond_abs_iso
A26 = (1/(M_ISO*CP_ISO))*(A_ABS_ISO*h_cond_abs_iso + A_TUBO_ISO*h_cond_tubo_iso + A_ISO*h_conv_iso_amb + A_ISO*h_rad_iso_ground)
A27 = (1/(M_ISO*CP_ISO))*A_TUBO_ISO*h_cond_tubo_iso
A28 = (1/(M_ISO*CP_ISO))*A_ISO*(h_conv_iso_amb*Tamb + h_rad_iso_ground*T_GROUND)
#DEFINE MODEL EQUATIONS - ODES - (GLASS, PV CELL, TEDLAR, ABSORBER, TUBE, FLUID, INSULATION) # dT1dt = A1*G_ajustado - A2*x[0] + A3*x[1] + A4 # dT2dt = A5*G_ajustado - A6*G_ajustado + A7*x[0] - A8*x[1] + A9*x[2]# dT3dt = A10*G_ajustado - A11*x[2] + A12*x[1] +A13*x[3]
def SysEdo(x, k):#tv-x[0] tcel-x[1] ttedlar-x[2] tabs-x[3] ttubo-x[4] tiso-x[5] tfs-x[6]
dT1dt = A1*polyval(k,rev_curve) - A2*x[0] + A3*x[1] + A4
dT2dt = A5*polyval(k,rev_curve) - A6*polyval(k,rev_curve) + A7*x[0] - A8*x[1] + A9*x[2]
dT3dt = A10*polyval(k,rev_curve) - A11*x[2] + A12*x[1] +A13*x[3]
dT4dt = A14*x[2] - A15*x[3] + A16*x[4] + A17*x[5]
dT5dt = A18*x[3] - A19*x[4] + A20*x[6] + A20*T_F_ENT + A21*x[5]
dT6dt = A22*x[4] - A23*x[6] + A24
dT7dt = A25*x[3] - A26*x[5] + A27*x[4] + A28
Tdot = np.array([dT1dt, dT2dt, dT3dt, dT4dt, dT5dt, dT6dt, dT7dt])
return Tdot
#RungeKutta4
def RK4(f, x0, t0, tf, dt):
t = np.arange(t0, tf, dt) #time vector
nt = t.size #lenght of time vector
nx = x0.size #length of state variables?
x = np.zeros((nx,nt)) #initialize 2D vector
x[:,0] = x0 #initial conditions
#RK4 constants
for k in range(nt-1):
k1 = dt*f(t[k], x[:,k],k)
k2 = dt*f(t[k] + dt/2, x[:,k] + k1/2, k)
k3 = dt*f(t[k] + dt/2, x[:,k] + k2/2, k)
k4 = dt*f(t[k] + dt, x[:,k] + k3, k)
dx = (k1 + 2*k2 + 2*k2 + k4)/6
x[:,k+1] = x[:,k] + dx
return x,t
#Define problems
f = lambda t, x, k : SysEdo(x, k)
#initial state - t0 is initial time - tf is final time - dt is time step
x0 = np.array([30, 30, 30, 30, 30, 30, 30])
t0 = 0
tf = 1000
dt = 1
#EDO SOLVE
x, t = RK4(f, x0, t0, tf, dt)
plt.figure()
plt.plot(t, x[0], '-', label='Tvidro')
"""
plt.plot(t, x[1], '-', label='Tpv')
plt.plot(t, x[2], '-', label='Ttedlar')
plt.plot(t, x[3], '-', label='Tabs')
plt.plot(t, x[4], '-', label='Tiso')
plt.plot(t, x[5], '-', label='Ttubo')
plt.plot(t, x[6], '-', label='Tfsai')"""
plt.title('Gráfico')
plt.legend(['Tvidro', 'Tpv', 'Ttedlar', 'Tabs', 'Tiso', 'Ttubo', 'Tfsai'], shadow=False)
plt.xlabel('t (s)')
plt.ylabel('Temperatura (°C)')
plt.xlim(0,20)
plt.ylim(0,150)
plt.grid('on')
plt.show()
Thank you in advance, I am also open to completely start the implementation from scratch if there is a better way to do this with python or matlab.
You can just replace
x, t = RK4(f, x0, t0, tf, dt)
with
t = arange(t0,tf+0.5*dt,dt)
res = solve_ivp(f,(t0,tf),x0,t_eval=t,args=(k,), method="DOP853", atol=1e-6,rtol=1e-8)
x = res.y[0]
Adapt the last 3 parameters to your liking.

Python matplotlib - set_data and set_3d_properties don't seem to be updating my plot

I am currently working on a Yee Solver script for uni, but when I try to animate my 3D graph, the graph is not what is expected. It works for a 2D plot, but I can't seem to translate that into 3D. From my understanding, set_data and set_3d_properties need a 1D array to work, which I am inputting.
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits import mplot3d
from matplotlib.widgets import Slider
# Program Variables
wv_lgth_num = 10
graph_type = '3d'
t = 0
# Physical Constants
c = 3e8
mu_r = 1
eps_r = 1
# Source Constants
f = 2e9
omega = 2*f*(np.pi)
amp = 1.0
wv_lgth = c/f
period = 1/f
# Step size
dz = wv_lgth/20
dt = ((c/f)/20)/c
#dt = ((1/f)/20)/1
# Axis Grids
z_grid = np.arange(0,wv_lgth_num*wv_lgth,dz)
t_grid = np.arange(0,10*period,dt)
# Number of steps
num_z = z_grid.size
num_t = t_grid.size
# Coefficients
coe_E = c*dt/(eps_r*dz)
coe_H = c*dt/(mu_r*dz)
# E and H Matricies
E_mat = np.zeros((num_z,num_t))
H_mat = np.zeros((num_z,num_t))
# Generating Values for E and H
for time in range(0,num_t-1):
for pos in range(0,num_z-1):
# Source Wave
if pos == 0:
H_mat[0,time] = amp*np.sin(omega*t_grid[time])
# All cases of Yee Solver
if pos == 1:
if time == 0:
H_mat[1,0] = 0
E_mat[0,0] = 0
else:
H_mat[1,time] = H_mat[1,time-1] + coe_H*(E_mat[1,time-1] - E_mat[0,time-1])
E_mat[0,time] = E_mat[0,time-1] + coe_E*(H_mat[1,time] - H_mat[0,time])
if pos > 1 and pos != num_z-1:
if time == 0:
H_mat[pos,0] = 0
E_mat[pos-1,0] = 0
if time > 0:
H_mat[pos,time] = H_mat[pos,time-1] + coe_H*(E_mat[pos,time-1] - E_mat[pos-1,time-1])
E_mat[pos-1,time] = E_mat[pos-1,time-1] + coe_E*(H_mat[pos,time] - H_mat[pos-1,time])
if pos == num_z-1:
if time == 0:
H_mat[num_z-1,0] = 0
E_mat[num_z-2,0] = 0
E_mat[num_z-1,0] = 0
if time > 0:
H_mat[num_z-1,time] = H_mat[num_z-1,time-1] + coe_H*(E_mat[num_z-1,time-1] - E_mat[num_z-2,time-1])
E_mat[num_z-2,time] = E_mat[num_z-2,time-1] + coe_E*(H_mat[num_z-1,time] - H_mat[num_z-2,time])
E_mat[num_z-1,time] = E_mat[num_z-2,time]
def update(val):
t = slider_time.val
if graph_type == '2d':
a.set_ydata(E_mat[:,t])
b.set_ydata(H_mat[:,t])
if graph_type == '3d':
a.set_3d_properties(E_mat[:,t])
a.set_data(z_grid,np.zeros((num_z,num_t))[:,t])
b.set_3d_properties(np.zeros((num_z,num_t))[:,t])
b.set_data(z_grid,H_mat[:t])
fig.canvas.draw_idle()
print(H_mat)
print(H_mat[:,t].size)
print(z_grid)
print(np.zeros((num_z,num_t))[:,t].size)
# Creating plot
if graph_type == '3d':
fig, ax = plt.subplots()
ax = plt.axes(projection='3d')
b, = ax.plot3D(z_grid,H_mat[:,t],np.zeros((num_z,num_t))[:,t], label='H')
a, = ax.plot3D(z_grid,np.zeros((num_z,num_t))[:,t],E_mat[:,t], label='E')
plt.title('Light Wave')
ax.set_xlabel('z')
ax.set_ylabel('x')
ax.set_zlabel('y')
plt.legend()
ax_time = plt.axes([0.25,0.1,0.65,0.03])
slider_time = Slider(ax_time,'Time',0,num_t-2,valinit=0,valstep=1)
slider_time.on_changed(update)
plt.show()
if graph_type == '2d':
fig, ax = plt.subplots()
plt.subplots_adjust(left=0.25, bottom=0.25)
a, = plt.plot(z_grid,E_mat[:,t], label='E (yz plane)')
b, = plt.plot(z_grid,H_mat[:,t], label='H (xz plane)')
plt.title('Light Wave')
plt.xlabel('z')
plt.ylabel('x')
plt.legend()
ax_time = plt.axes([0.25,0.1,0.65,0.03])
slider_time = Slider(ax_time,'Time',0,num_t-2,valinit=0,valstep=1)
slider_time.on_changed(update)
plt.show()
Any help would be appreciated. The middle for loop is just generating my functions, using the Yee Method.

Earth&Moon orbit system. My data is wrong

There is my code. I fixed it like this:
# Take 3 digits for significant figures in this code
import numpy as np
from math import *
from astropy.constants import *
import matplotlib.pyplot as plt
import time
start_time = time.time()
"""
G = Gravitational constant
g0 = Standard acceleration of gravity ( 9.8 m/s2)
M_sun = Solar mass
M_earth = Earth mass
R_sun = Solar darius
R_earth = Earth equatorial radius
au = Astronomical unit
Astropy.constants doesn't have any parameter of moon.
So I bring the data from wikipedia(https://en.wikipedia.org/wiki/Moon)
"""
M_moon = 7.342E22
R_moon = 1.737E6
M_earth = M_earth.value
R_earth = R_earth.value
G = G.value
perigee, apogee = 3.626E8, 4.054E8
position_E = np.array([0,0])
position_M = np.array([(perigee+apogee)/2.,0])
position_com = (M_earth*position_E+M_moon*position_M)/(M_earth+M_moon)
rel_pE = position_E - position_com
rel_pM = position_M - position_com
F = G*M_moon*M_earth/(position_M[0]**2)
p_E = {"x":rel_pE[0], "y":rel_pE[1],"v_x":0, "v_y":(float(F*rel_pE[0])/M_earth)**.5}
p_M = {"x":rel_pM[0], "y":rel_pM[1],"v_x":0, "v_y":(float(F*rel_pM[0])/M_moon)**.5}
print(p_E, p_M)
t = range(0,365)
data_E , data_M = [], []
def s(initial_velocity, acceleration, time):
result = initial_velocity*time + 0.5*acceleration*time**2
return result
def v(initial_velocity, acceleration, time):
result = initial_velocity + acceleration*time
return result
dist = float(sqrt((p_E["x"]-p_M['x'])**2 + (p_E["y"]-p_M["y"])**2))
xE=[]
yE=[]
xM=[]
yM=[]
data_E, data_M = [None]*len(t), [None]*len(t)
for i in range(1,366):
data_E[i-1] = p_E
data_M[i-1] = p_M
dist = ((p_E["x"]-p_M["x"])**2 + (p_E["y"]-p_M["y"])**2)**0.5
Fg = G*M_moon*M_earth/(dist**2)
theta_E = np.arctan(p_E["y"]/p_E["x"])
theta_M = theta_E + np.pi #np.arctan(data_M[i-1]["y"]/data_M[i-1]["x"])
Fx_E = Fg*np.cos(theta_E)
Fy_E = Fg*np.sin(theta_E)
Fx_M = Fg*np.cos(theta_M)
Fy_M = Fg*np.sin(theta_M)
a_E = Fg/M_earth
a_M = Fg/M_moon
v_E = (p_E["v_x"]**2+p_E["v_y"]**2)**.5
v_M = (p_M["v_x"]**2+p_M["v_y"]**2)**.5
p_E["v_x"] = v(p_E["v_x"], Fx_E/M_earth, 24*3600)
p_E["v_y"] = v(p_E["v_y"], Fy_E/M_earth, 24*3600)
p_E["x"] += s(p_E['v_x'], Fx_E/M_earth, 24*3600)
p_E["y"] += s(p_E['v_y'], Fy_E/M_earth, 24*3600)
p_M["v_x"] = v(p_M["v_x"], Fx_M/M_moon, 24*3600)
p_M["v_y"] = v(p_M["v_y"], Fy_M/M_moon, 24*3600)
p_M["x"] += s(p_M['v_x'], Fx_M/M_moon, 24*3600)
p_M["y"] += s(p_M['v_y'], Fy_M/M_moon, 24*3600)
for i in range(0,len(t)):
xE += data_E[i]["x"]
yE += data_E[i]["y"]
xM += data_M[i]["x"]
yM += data_M[i]["y"]
print("\n Run time \n --- %d seconds ---" %(time.time()-start_time))
after run this code i tried to print data_E and data_M.
Then I can get data but there is no difference. All of the data is the same.
But when I printed data step by step, it totally different.
I have wrong data problem and increase distance problem. Please help me this problem..
The code exits near line 45, where you are trying to assign p_E by pulling the square root of a negative number on the right hand side (as you've moved the [0] coordinate of the Earth to negative values while shifting Earth and Moon into the coordinate system of their center of mass). In line 45, the value of F*rel_pE[0]/M_earth is negative. So the code never reaches the end of the program using python 2.7.14. That bug needs to be solved before trying to discuss any further aspects.

Magnus Force, Drag force , Serve Ball Trajectory

I am trying to put into this code. Main focus for the code would be to combine all of the forces, hitting at various launch angles and print out the graph of figure 42.3.
from numpy import *
from matplotlib import*
from matplotlib.pyplot import *
from __future__ import division
Basic info
Dimeter = 0.067
r = (Dimeter/2) # radius of sphere (meters)
s = 1.0 # spin in revolutions per second (positive is backspin)
p = 1.225 # air density in kg/m^3
dragCoef = 0.5 # drag coefficient
m = 0.0585 # mass of the ball in kilograms
g = 9.82 # gravitational constant
dt = 0.01
A = (pi*r**2)
Cd = 0.5
Cl = 1.5
v = 30
t = 0.470
n= (t/dt)
a = zeros(n)
v = zeros(n)
x = zeros(n)
Fg = zeros(n)
Fd = zeros(n)
t = zeros(n)
v[0] = 0
x[0] = 0
i = 0
A while loop to add Forces on the ball
while i <= (n-2):
Fg[i] = (m*g)
Fd[i] = (.5*p*A*Cd*(v[i]**2)*sign(-v[i]))
a[i] = ((Fg[i] + Fd[i]) / m)
v[i+1] = (v[i] + a[i]*dt)
x[i+1] = (x[i] +v[i]*dt +.5*a[i]*(dt**2))
t[i+1] = (t[i] + dt)
i = i+1
Printing out graph
print "My distance is",max(x)-min(x), "meters"
print "At t=", argmax(x)/100, "s"
plot(x,label="position")
legend()

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