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I need help with the following code, specifically at Step 6 ( repeating the above with no noise ) . I cannot get the amplitude

I need help with the following code, specifically at Step 6(repeating the above with no noise).I cannot get the amplitude time series to plot all 9 graphs exactly the same; the y axis values value between all of the EOFs. They should be exactly the same if it is only based on the signal.
import numpy as np
import matplotlib.pyplot as plt
# Step 1: Define Parameters
T =24 # hours
N =9 # locations
Dt =1 # hour
omega =2* np.pi / T
#Step 6: Repeat with no noise
# Function to generate data
def u(x, y, t, a, b, c, alpha):
return (a + b * x + c)* np.cos(alpha * t)* np.cos(2* omega * t)
# Generate data samples
np.random.seed(42) # Set a consistent random seed
x_values_NN = y_values_NN = np.random.rand(N)
t_values_NN = np.arange(0, T, Dt)
data_NN = np.zeros((N, N, len(t_values_NN)))
for i in range(N):
for j in range(N):
for k in range(len(t_values_NN)):
data_NN[i, j, k]= u(x_values_NN[i], y_values_NN[j], t_values_NN[k],1,2,3,0.1)
# Step 3: Perform EOF analysis
correlation_matrix_NN = np.corrcoef(data_NN.reshape((N * N, len(t_values_NN))))
eigenvalues_NN, eigenvectors_NN = np.linalg.eig(correlation_matrix_NN)
sorted_indices_NN = np.argsort(eigenvalues_NN)[::-1]
eigenvalues_NN = eigenvalues_NN[sorted_indices_NN]
eigenvectors_NN = eigenvectors_NN[:, sorted_indices_NN]
# Ensure eigenvectors are real
eigenvectors_NN = np.real(eigenvectors_NN)
# Plot the eigenvectors
for i in range(N):
plt.subplot(3,3, i +1)
plt.imshow(np.real(eigenvectors_NN[:, i]).reshape((N, N)), cmap='viridis')
plt.title(f'EOF Mode {i +1}')
# Map the eigenvectors
for i in range(N):
plt.subplot(3,3, i +1)
# Reshape the eigenvector to the spatial grid
eigenvector_map_NN = np.real(eigenvectors_NN[:, i]).reshape((N, N))
# Create a contour plot
plt.contourf(eigenvector_map_NN, cmap='viridis')
plt.title(f'EOF Mode {i +1}')
plt.savefig(f'EOF_Mode_{i +1}.png', dpi=600)
# Calculate amplitude of time series
amplitude_NN = np.abs(np.dot(eigenvectors_NN.T, data_NN.reshape((N * N, len(t_values_NN)))))
# Plot the amplitude time series for each mode
amplitude_NN = np.abs(np.dot(eigenvectors_NN.T, data_NN.reshape((N * N, len(t_values_NN)))))
for i in range(N):
plt.figure()
plt.plot(t_values_NN, amplitude_NN[i, :])
plt.title(f'Amplitude Time Series (No Noise) for Mode {i +1}')
plt.xlabel('Time (Hours)')
plt.ylabel('Amplitude')
# Save the amplitude plot with the mode number in the filename
plt.savefig(f'Amplitude_NoNoise_Mode{i +1}.png', dpi=600)
# Show the correlation between A1(t) and A2(t)
corr_12_NN = np.corrcoef(amplitude_NN[0, :], amplitude_NN[1, :])[0,1]
plt.figure()
plt.plot(np.arange(len(t_values_NN)),[corr_12_NN]* len(t_values_NN))
plt.title('Correlation between A1(t) and A2(t) with No Noise')
plt.xlabel('Time (Hours)')
plt.ylabel('Amplitude')
# Save the correlation plot
plt.savefig('Correlation_NoNoise.png', dpi=600)
# Show or save the plots as needed
plt.show()

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