import numpy as np
import matplotlib.pyplot as plt

data = np.genfromtxt('xrd_lab.txt')

bolgelengde = 0.7093e-10
k = 2 * np.pi / bolgelengde

theta = data[:,0] * (np.pi/180)

Q = 2 * k * np.sin(theta)
I = data[:, 1]

plt.plot(Q, I)
plt.xlabel(r'$\vert Q \vert$ [m]')
plt.ylabel('Intensity [a.u.]')
plt.savefig('Q_I_plot')
plt.show()