def evalnfit(f, x, xx): """\ evalnfit(f, x, xx): f = function being tested x = grid points xx = points for interpolation returns y, yy where y = f(x) and yy are interpolated at xx """ assert isinstance(x, np.ndarray) and isinstance(xx, np.ndarray) y = np.empty(x.shape) for i,g in enumerate(x): y[i] = f(x[i]) yy = lgrng.interp(x, y, xx) return y, yy
import numpy as np
from matplotlib import pyplot as plt
import sys, os
sys.path.append(os.getcwd() + "/..")
import gridpts
import lgrng
x = gridpts.cheb(20)
y = np.sin(np.sin(x))
plt.plot(x, y, "ro")
xx = gridpts.unif(200)
xx = xx * 0.999 + 1e-6
yy = lgrng.interp(x, y, xx)
plt.plot(xx, yy, "k")
plt.axis("tight")
plt.show()
