import matplotlib.pyplot as plt
import numpy as np

def double_exponential(x, A, B, alpha, Gamma1, beta1, Gamma2, beta2):
    return A*(1-alpha*np.exp(-(Gamma1*x)**beta1)-(1-alpha)*np.exp(-(Gamma2*x)**beta2))+B

x = np.logspace(-2, 2, num=200)

y1 = double_exponential(x, 1, 0, 0.5, 0.1, 1, 10, 1)
plt.semilogx(x, y1, 'b-')
plt.xlabel(r'$\Delta t$')
plt.ylabel(r'$D(\Delta t)$')
plt.show()