import numpy as np
import matplotlib.pyplot as plt

F = np.linspace(0.05,0.95, 100)

X = np.zeros((len(F),len(F)), dtype=np.float64)

for i1,f1 in enumerate(F):
    for i2,f2 in enumerate(F):
        X[i1,i2] = np.log(f1*(1-f2)/(f2*(1-f1)))

plt.clf()
im = plt.imshow(X, origin='lower', extent=(min(F),max(F),min(F),max(F)),\
          cmap="PiYG")
plt.xlabel(r"$P(X|A)$", size=18)
plt.ylabel(r"$P(X|B)$", size=18)
V = [-3,-2,-1,0,1,2,3]
CS = plt.contour(X, V, origin='lower',\
                 extent=(min(F),max(F),min(F),max(F)), colors='k',\
                linestyles='solid')
plt.colorbar(im)
plt.clabel(CS, V, fmt="%3.1f")
plt.grid(True)
plt.xlim(0.05,0.95)
plt.ylim(0.05,0.95)
plt.savefig("odds_ratio_map.pdf")
plt.savefig("odds_ratio_map.svg")