check_derivative(fctn, x0, num=7, plotIt=True, dx=None, expectedOrder=2, tolerance=0.85, eps=1e-10, ax=None)¶
Basic derivative check
Compares error decay of 0th and 1st order Taylor approximation at point x0 for a randomized search direction.
fctn (callable) – function handle
x0 (numpy.ndarray) – point at which to check derivative
num (int) – number of times to reduce step length, h
plotIt (bool) – if you would like to plot
dx (numpy.ndarray) – step direction
expectedOrder (int) – The order that you expect the derivative to yield.
tolerance (float) – The tolerance on the expected order.
eps (float) – What is zero?
- Return type
did you pass the test?!
from discretize import tests, utils import numpy as np def simplePass(x): return np.sin(x), utils.sdiag(np.cos(x)) tests.checkDerivative(simplePass, np.random.randn(5))