########################################################
# Demonstration of interpolation for Hercule's cyborg
# prints three plots for different input data and resulting
# interpolations
#
#
# JHPS
# C: 22/10/2013
#######################################################
import numpy as np
from scipy.interpolate import Rbf
import matplotlib.pyplot as plt
from matplotlib import cm
### After first walk with points A, B and C
x = np.array([-1,1.5,-1])
y = np.array([1,0,-1])
z = np.array([5,0,-5])
ti = np.linspace(-2.0, 2.0, 100)
XI, YI = np.meshgrid(ti, ti)
# Interpolation
rbf = Rbf(x, y, z, epsilon=2)
ZI = rbf(XI, YI)
# Plotting
plt.figure()
n = plt.normalize(-2., 2.)
plt.subplot(1, 1, 1)
plt.pcolor(XI, YI, ZI, cmap=cm.jet)
plt.scatter(np.array([0]), np.array([0]), s=100, facecolors='none', edgecolors='k')
plt.scatter(x, y, 100, z, cmap=cm.jet)
plt.plot(np.array([0]),np.array([0]))
plt.xlim(-2, 2)
plt.ylim(-2, 2)
plt.colorbar()
labels = ['A','B','C']
for i in range(len(x)):
plt.annotate(labels[i], xy=(x[i], y[i]), xycoords='data',
xytext=(-20, 10), textcoords='offset points',
arrowprops=dict(arrowstyle="->")
)
plt.annotate('D', xy=(0, 0), xycoords='data',
xytext=(-20, 10), textcoords='offset points',
arrowprops=dict(arrowstyle="->")
)
# Second walk with another point between A and B
x = np.array([-1,1.5,-1,0.5])
y = np.array([1,0,-1,1.5])
z = np.array([5,0,-5,3])
ti = np.linspace(-2.0, 2.0, 100)
XI, YI = np.meshgrid(ti, ti)
# Interpolation
rbf = Rbf(x, y, z, epsilon=2)
ZI = rbf(XI, YI)
# Plotting
plt.figure()
n = plt.normalize(-2., 2.)
plt.subplot(1, 1, 1)
plt.pcolor(XI, YI, ZI, cmap=cm.jet)
plt.scatter(np.array([0]), np.array([0]), s=100, facecolors='none', edgecolors='k')
plt.scatter(x, y, 100, z, cmap=cm.jet)
plt.plot(np.array([0]),np.array([0]))
plt.xlim(-2, 2)
plt.ylim(-2, 2)
plt.colorbar()
plt.annotate('New point', xy=(x[-1], y[-1]), xycoords='data',
xytext=(20, -10), textcoords='offset points',
arrowprops=dict(arrowstyle="->")
)
plt.annotate('D', xy=(0, 0), xycoords='data',
xytext=(-20, 10), textcoords='offset points',
arrowprops=dict(arrowstyle="->")
)
# Third walk with another point before A
x = np.array([-1.5,-1,1.5,-1])
y = np.array([1.5,1,0,-1])
z = np.array([-5,5,0,-5])
ti = np.linspace(-2.0, 2.0, 100)
XI, YI = np.meshgrid(ti, ti)
# Interpolation
rbf = Rbf(x, y, z, epsilon=2)
ZI = rbf(XI, YI)
# Plotting
plt.figure()
n = plt.normalize(-2., 2.)
plt.subplot(1, 1, 1)
plt.pcolor(XI, YI, ZI, cmap=cm.jet)
plt.scatter(np.array([0]), np.array([0]), s=100, facecolors='none', edgecolors='k')
plt.scatter(x, y, 100, z, cmap=cm.jet)
plt.plot(np.array([0]),np.array([0]))
plt.xlim(-2, 2)
plt.ylim(-2, 2)
plt.colorbar()
plt.annotate('a different new point', xy=(x[0], y[0]), xycoords='data',
xytext=(20, 0), textcoords='offset points',
arrowprops=dict(arrowstyle="->")
)
plt.annotate('D', xy=(0, 0), xycoords='data',
xytext=(-20, 10), textcoords='offset points',
arrowprops=dict(arrowstyle="->")
)
## show plots
plt.show()
