wave = cnt.c / freq * convert(unit_in="m", unit_out="mm")
px = np.linspace(-1, 1, opt.nxy[0]) * opt.lxy / 2
py = np.linspace(-1, 1, opt.nxy[1]) * opt.lxy / 2
mesh = np.meshgrid(px, py)
x, y = mesh[0], mesh[1]
r, t = np.sqrt(x**2 + y**2), np.arctan(y / x)
m, n = opt.mn
a, b = opt.radi
pr = np.linspace(10, 50, 1000)
m = 5
n = 10
print(jn_zeros(m, n)[-1])
print(jnp_zeros(m, n)[-1])
print(yn_zeros(m, n)[-1])
print(ynp_zeros(m, n)[-1])
x0_mn_1 = jn_zeros(m, 5)[-1]
x1_mn_1 = jnp_zeros(m, 5)[-1]
x0_mn_2 = jn_zeros(m, 7)[-1]
x1_mn_2 = jnp_zeros(m, 7)[-1]
d_1 = jvp(m, pr, 0) * yvp(m, x1_mn_1, 1) - \
yvp(m, pr, 0) * jvp(m, x1_mn_1, 1)
d_2 = jvp(m, pr, 0) * yvp(m, x1_mn_2, 1) - \
yvp(m, pr, 0) * jvp(m, x1_mn_2, 1)
plt.figure()
plt.plot(pr, d_1)
plt.plot(pr, d_2)
txt = "{:d}".format(nth)
txt += "\t{:.2f}\t{:.2f}\t{:.2f}".format(val, jn(0, val), jn(1, val))
print(txt)
for nth, val in enumerate(jn_zeros(2, 5)):
txt = "{:d}".format(nth)
txt += "\t{:.2f}\t{:.2f}\t{:.2f}".format(val, jn(0, val), jn(1, val))
txt += "\t{:.2f}".format(jn(2, val))
print(txt)
"""Compute zeros of integer-order Bessel function derivative Jn'(x).
"""
print(jnp_zeros(0, 5))
print(jnp_zeros(1, 5))
print(jnp_zeros(2, 5))
"""Compute zeros of integer-order Bessel function Yn(x).
"""
print(yn_zeros(0, 5))
print(yn_zeros(1, 5))
print(yn_zeros(2, 5))
"""Compute zeros of integer-order Bessel function derivative Yn'(x).
"""
print(ynp_zeros(0, 5))
print(ynp_zeros(1, 5))
print(ynp_zeros(2, 5))
"""Compute zeros of integer-order Bessel functions Jn and Jn'.
Parameters
----------
nt : int
Number (<=1200) of zeros to compute
Returns
px = np.linspace(-1, 1, opt.nxy[0]) * opt.lxy / 2
py = np.linspace(-1, 1, opt.nxy[1]) * opt.lxy / 2
mesh = np.meshgrid(px, py)
x, y = mesh[0], mesh[1]
r, t = np.sqrt(x**2 + y**2), np.arctan(y / x)
m, n = opt.mn
a, b = opt.radi
pr = np.linspace(20, 100.0, 1000)
r0 = np.linspace(0.2, 1, 1000)
m = 31
n = 5
print(jn_zeros(m, n))
print(jnp_zeros(m, n))
print(yn_zeros(m, n))
print(ynp_zeros(m, n))
plt.figure()
#plt.plot(pr, jn_dev(r0, 37, 12, 0) - nj_dev(r0, 37, 12, 0))
plt.plot(pr, jn_dev(r0, 31, 10, 0) - nj_dev(r0, 31, 10, 0))
plt.plot(pr, jn_dev(r0, 31, 11, 0) - nj_dev(r0, 31, 11, 0))
plt.xlim(0, 100)
plt.ylim(-0.025, 0.025)
plt.grid()
plt.figure()
#plt.plot(pr, jn_dev(r0, 37, 12, 1) - nj_dev(r0, 37, 12, 1))
plt.plot(pr, jn_dev(r0, 31, 10, 1) - nj_dev(r0, 31, 10, 1))
plt.plot(pr, jn_dev(r0, 31, 11, 1) - nj_dev(r0, 31, 11, 1))
plt.grid()
@author: shiyanlou
"""
# %matplotlib qt
from scipy import linspace
from scipy.special import jn, yn, jn_zeros, yn_zeros
import matplotlib.pyplot as plt
n = 0
x = 0.0
# Bessel function of first kind
print "J_%d(%f) = %f" % (n, x, jn(n, x))
x = 1.0
# Bessel function of second kind
print "Y_%d(%f) = %f" % (n, x, yn(n, x))
x = linspace(0, 10, 100)
fig, ax = plt.subplots()
for n in range(4):
ax.plot(x, jn(n, x), label=r"$J_%d(x)$" % n)
ax.legend()
fig.show()
n = 0
m = 4
print jn_zeros(n, m)
print yn_zeros(n, m)