spline interpolation and draw image by matplotlib

 1 # spline interpolation and draw image by matplotlib

 from scipy import interpolate
 import matplotlib.pyplot as plt

 #prepare data of globe
 x_g = [, , , , , ]
 y_g = [,,,,,]

 x_points=x_g.copy()
 y_points=y_g.copy()

 # spline interpolation
 def f(x):
     tck = interpolate.splrep(x_points, y_points)
     return interpolate.splev(x, tck)

 # a test point  1.25/ ret=f(1.25)
 p1=f(1.25)
 print(p1.tolist()) # ndarray to list
 x_g.append(1.25)
 y_g.append(p1.tolist())

 # another test point  [2.6,3.1,4.5]/ ret=f(m)
 m=[2.6,3.1,4.5]
 n=f(m)
 print(f(m))
 x_g.extend(m)
 y_g.extend(n)

 x_g.sort()
 y_g.sort()
 plt.plot(x_g,y_g)
 plt.gray()
 plt.grid(True)

 # add label for each point
 for i in range(,len(x_g)):
     plt.text(x_g[i],y_g[i],str([x_g[i],y_g[i]]), family='serif', style='italic', ha='right', wrap=True)

 plt.show()