def show_x_with_unobserved():
""" shows x=1,2,3 with velocity superimposed on top """
# plot velocity
sigma=[0.5,1.,1.5,2]
cov = np.array([[1,1],[1,1.1]])
stats.plot_covariance_ellipse ((2,2), cov=cov, variance=sigma, axis_equal=False)
# plot positions
cov = np.array([[0.003,0], [0,12]])
sigma=[0.5,1.,1.5,2]
e = stats.covariance_ellipse (cov)
stats.plot_covariance_ellipse ((1,1), ellipse=e, variance=sigma, axis_equal=False)
stats.plot_covariance_ellipse ((2,1), ellipse=e, variance=sigma, axis_equal=False)
stats.plot_covariance_ellipse ((3,1), ellipse=e, variance=sigma, axis_equal=False)
# plot intersection cirle
isct = Ellipse(xy=(2,2), width=.2, height=1.2, edgecolor='r', fc='None', lw=4)
plt.gca().add_artist(isct)
plt.ylim([0,11])
plt.xlim([0,4])
plt.xticks(np.arange(1,4,1))
plt.xlabel("Position")
plt.ylabel("Time")
plt.show()
def show_x_error_chart(count):
""" displays x=123 with covariances showing error"""
plt.cla()
plt.gca().autoscale(tight=True)
cov = np.array([[0.03,0], [0,8]])
e = stats.covariance_ellipse (cov)
cov2 = np.array([[0.03,0], [0,4]])
e2 = stats.covariance_ellipse (cov2)
cov3 = np.array([[12,11.95], [11.95,12]])
e3 = stats.covariance_ellipse (cov3)
sigma=[1, 4, 9]
if count >= 1:
stats.plot_covariance_ellipse ((0,0), ellipse=e, variance=sigma)
if count == 2 or count == 3:
stats.plot_covariance_ellipse ((5,5), ellipse=e, variance=sigma)
if count == 3:
stats.plot_covariance_ellipse ((5,5), ellipse=e3, variance=sigma,
edgecolor='r')
if count == 4:
M1 = np.array([[5, 5]]).T
m4, cov4 = stats.multivariate_multiply(M1, cov2, M1, cov3)
e4 = stats.covariance_ellipse (cov4)
stats.plot_covariance_ellipse ((5,5), ellipse=e, variance=sigma,
alpha=0.25)
stats.plot_covariance_ellipse ((5,5), ellipse=e3, variance=sigma,
edgecolor='r', alpha=0.25)
stats.plot_covariance_ellipse (m4[:,0], ellipse=e4, variance=sigma)
#plt.ylim([0,11])
#plt.xticks(np.arange(1,4,1))
plt.xlabel("Position")
plt.ylabel("Velocity")
plt.show()