eturns ------- scalar or ndarray Values of the derivative of the Hankel function. See Also -------- hankel2 Notes ----- The derivative is computed using the relation DLFM 10.6.7 [2]_. References ---------- .. [1] Zhang, Shanjie and Jin, Jianming. "Computation of Special Functions", John Wiley and Sons, 1996, chapter 5. https://people.sc.fsu.edu/~jburkardt/f77_src/special_functions/special_functions.html .. [2] NIST Digital Library of Mathematical Functions. https://dlmf.nist.gov/10.6.E7 Examples -------- Compute the Hankel function of the second kind of order 0 and its first two derivatives at 1. >>> from scipy.special import h2vp >>> h2vp(0, 1, 0), h2vp(0, 1, 1), h2vp(0, 1, 2) ((0.7651976865579664-0.088256964215677j), (-0.44005058574493355-0.7812128213002889j), (-0.3251471008130329+0.8694697855159659j)) Compute the first derivative of the Hankel function of the second kind for several orders at 1 by providing an array for `v`. >>> h2vp([0, 1, 2], 1, 1) array([-0.44005059-0.78121282j, 0.3251471 -0.86946979j, 0.21024362-2.52015239j]) Compute the first derivative of the Hankel function of the second kind of order 0 at several points by providing an array for `z`. >>> import numpy as np >>> points = np.array([0.5, 1.5, 3.]) >>> h2vp(0, points, 1) array([-0.24226846-1.47147239j, -0.55793651-0.41230863j, -0.33905896+0.32467442j]) r