# coding: utf-8 # # Monomial interpolation # In[2]: import numpy as np import numpy.linalg as la import matplotlib.pyplot as pt # In[3]: x = np.linspace(0, 1, 200) # Now plot the monomial basis on the interval [0,1] up to $x^9$. # In[4]: n = 10 for i in range(n): pt.plot(x, x**i) pt.vlines(np.linspace(0, 1, n), 0, 1, alpha=0.5, linestyle="--") # * How do the entries of the Vandermonde matrix relate to this plot? # ------------------ # * Guess the condition number of the Vandermonde matrix for $n=5,10,20$: # In[5]: n = 5 V = np.array([np.linspace(0, 1, n)**i for i in range(n)]).T la.cond(V) # In[ ]: