# Python scipy.special.kv() Examples

The following are 30 code examples of scipy.special.kv(). You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may also want to check out all available functions/classes of the module , or try the search function .
Example #1
 Source File: generaSR.py    From ocelot with GNU General Public License v3.0 6 votes
```def flux_distrib(self):
"""

:return: flux in ph/sec/mrad**2/0.1%BW
"""
C_om = 1.3255e22 #ph/(sec * rad**2 * GeV**2 * A)
g = self.gamma
#self.eph_c = 1.
ksi = lambda w,t: 1./2.*w * (1. + g*g*t*t)**(3./2.)
F = lambda w, t: (1.+g*g*t*t)**2  * (1.+
g*g*t*t/(1.+g*g*t*t) * (kv(1./3.,ksi(w, t))/kv(2./3.,ksi(w, t)))**2)

dw_over_w = 0.001  # 0.1% BW
mrad2 = 1e-6 # transform rad to mrad
I = lambda eph, theta: mrad2*C_om * self.energy**2*self.I* dw_over_w* (eph/self.eph_c)**2 * kv(2./3.,ksi(eph/self.eph_c,theta))**2 * F(eph/self.eph_c, theta)
return I ```
Example #2
 Source File: test_basic.py    From Computable with MIT License 6 votes
```def test_ticket_854(self):
"""Real-valued Bessel domains"""
assert_(isnan(special.jv(0.5, -1)))
assert_(isnan(special.iv(0.5, -1)))
assert_(isnan(special.yv(0.5, -1)))
assert_(isnan(special.yv(1, -1)))
assert_(isnan(special.kv(0.5, -1)))
assert_(isnan(special.kv(1, -1)))
assert_(isnan(special.jve(0.5, -1)))
assert_(isnan(special.ive(0.5, -1)))
assert_(isnan(special.yve(0.5, -1)))
assert_(isnan(special.yve(1, -1)))
assert_(isnan(special.kve(0.5, -1)))
assert_(isnan(special.kve(1, -1)))
assert_(isnan(special.airye(-1)[0:2]).all(), special.airye(-1))
assert_(not isnan(special.airye(-1)[2:4]).any(), special.airye(-1)) ```
Example #3
 Source File: test_mpmath.py    From Computable with MIT License 6 votes
```def test_besselk(self):
def mpbesselk(v, x):
r = float(mpmath.besselk(v, x, **HYPERKW))
if abs(r) > 1e305:
# overflowing to inf a bit earlier is OK
r = np.inf * np.sign(r)
if abs(v) == abs(x) and abs(r) == np.inf and abs(x) > 1:
# wrong result (kv(x,x) -> 0 for x > 1),
# try with higher dps
old_dps = mpmath.mp.dps
mpmath.mp.dps = 200
try:
r = float(mpmath.besselk(v, x, **HYPERKW))
finally:
mpmath.mp.dps = old_dps
return r
assert_mpmath_equal(sc.kv,
_exception_to_nan(mpbesselk),
[Arg(-1e100, 1e100), Arg()]) ```
Example #4
 Source File: test_basic.py    From GraphicDesignPatternByPython with MIT License 6 votes
```def test_ticket_854(self):
"""Real-valued Bessel domains"""
assert_(isnan(special.jv(0.5, -1)))
assert_(isnan(special.iv(0.5, -1)))
assert_(isnan(special.yv(0.5, -1)))
assert_(isnan(special.yv(1, -1)))
assert_(isnan(special.kv(0.5, -1)))
assert_(isnan(special.kv(1, -1)))
assert_(isnan(special.jve(0.5, -1)))
assert_(isnan(special.ive(0.5, -1)))
assert_(isnan(special.yve(0.5, -1)))
assert_(isnan(special.yve(1, -1)))
assert_(isnan(special.kve(0.5, -1)))
assert_(isnan(special.kve(1, -1)))
assert_(isnan(special.airye(-1)[0:2]).all(), special.airye(-1))
assert_(not isnan(special.airye(-1)[2:4]).any(), special.airye(-1)) ```
Example #5
 Source File: covfunc.py    From pyGPGO with MIT License 6 votes
```def K(self, X, Xstar):
"""
Computes covariance function values over `X` and `Xstar`.

Parameters
----------
X: np.ndarray, shape=((n, nfeatures))
Instances
Xstar: np.ndarray, shape=((n, nfeatures))
Instances

Returns
-------
np.ndarray
Computed covariance matrix.
"""
r = l2norm_(X, Xstar)
bessel = kv(self.v, np.sqrt(2 * self.v) * r / self.l)
f = 2 ** (1 - self.v) / gamma(self.v) * (np.sqrt(2 * self.v) * r / self.l) ** self.v
res = f * bessel
res[np.isnan(res)] = 1
res = self.sigmaf * res + self.sigman * kronDelta(X, Xstar)
return (res) ```
Example #6
 Source File: ipol.py    From wradlib with MIT License 6 votes
```def cov_mat(h, sill=1.0, rng=1.0, shp=0.5):
"""matern covariance function"""
"""Matern Covariance Function Family:
shp = 0.5 --> Exponential Model
shp = inf --> Gaussian Model
"""
h = np.asanyarray(h)

# for v > 100 shit happens --> use Gaussian model
if shp > 100:
c = cov_gau(h, sill, rng)
else:
# modified bessel function of second kind of order v
kv = special.kv
# Gamma function
tau = special.gamma

fac1 = h / rng * 2.0 * np.sqrt(shp)
fac2 = tau(shp) * 2.0 ** (shp - 1.0)

c = np.where(h != 0, sill * 1.0 / fac2 * fac1 ** shp * kv(shp, fac1), sill)

return c ```
Example #7
 Source File: generaSR.py    From ocelot with GNU General Public License v3.0 5 votes
```def flux_total(self):
C_fi = 3.9614e19 #ph/(sec * rad * GeV * A)
mrad = 1e-3 # transform rad to mrad
S = lambda w: 9.*sqrt(3)/8./pi*w*simps(kv(5./3.,linspace(w, 20, num=200)))
F = lambda eph: mrad*C_fi*self.energy*self.I*eph/self.eph_c*S(eph/self.eph_c)
return F ```
Example #8
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def _check_kv(self):
cephes.kv(1,1) ```
Example #9
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def test_k0(self):
ozk = special.k0(.1)
ozkr = special.kv(0,.1)
assert_almost_equal(ozk,ozkr,8) ```
Example #10
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def test_k1(self):
o1k = special.k1(.1)
o1kr = special.kv(1,.1)
assert_almost_equal(o1k,o1kr,8) ```
Example #11
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def test_negv_kv(self):
assert_equal(special.kv(3.0, 2.2), special.kv(-3.0, 2.2)) ```
Example #12
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def test_kv0(self):
kv0 = special.kv(0,.2)
assert_almost_equal(kv0, 1.7527038555281462, 10) ```
Example #13
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def test_kv2(self):
kv2 = special.kv(2,0.2)
assert_almost_equal(kv2, 49.51242928773287, 10) ```
Example #14
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def test_kv_largearg(self):
assert_equal(special.kv(0, 1e19), 0) ```
Example #15
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def test_kve(self):
kve1 = special.kve(0,.2)
kv1 = special.kv(0,.2)*exp(.2)
assert_almost_equal(kve1,kv1,8)
z = .2+1j
kve2 = special.kve(0,z)
kv2 = special.kv(0,z)*exp(z)
assert_almost_equal(kve2,kv2,8) ```
Example #16
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def test_kvp_v0n1(self):
z = 2.2
assert_almost_equal(-special.kv(1,z), special.kvp(0,z, n=1), 10) ```
Example #17
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def test_kvp_n1(self):
v = 3.
z = 2.2
xc = -special.kv(v+1,z) + v/z*special.kv(v,z)
x = special.kvp(v,z, n=1)
assert_almost_equal(xc, x, 10)   # this function (kvp) is broken ```
Example #18
 Source File: test_basic.py    From Computable with MIT License 5 votes
```def test_kv_cephes_vs_amos(self):
self.check_cephes_vs_amos(special.kv, special.kn, rtol=1e-9, atol=1e-305)
self.check_cephes_vs_amos(special.kv, special.kv, rtol=1e-9, atol=1e-305) ```
Example #19
 Source File: test_mpmath.py    From Computable with MIT License 5 votes
```def test_besselk_complex(self):
assert_mpmath_equal(lambda v, z: sc.kv(v.real, z),
_exception_to_nan(lambda v, z: mpmath.besselk(v, z, **HYPERKW)),
[Arg(-1e100, 1e100), ComplexArg()]) ```
Example #20
 Source File: atmospheric_model.py    From hcipy with MIT License 5 votes
```def phase_covariance_von_karman(r0, L0):
'''Return a Field generator for the phase covariance function for Von Karman turbulence.

Parameters
----------
r0 : scalar
The Fried parameter.
L0 : scalar
The outer scale.

Returns
-------
Field generator
The phase covariance Field generator.
'''
def func(grid):
r = grid.as_('polar').r + 1e-10

a = (L0 / r0)**(5 / 3)
b = gamma(11 / 6) / (2**(5 / 6) * np.pi**(8 / 3))
c = (24 / 5 * gamma(6 / 5))**(5 / 6)
d = (2 * np.pi * r / L0)**(5 / 6)
e = kv(5 / 6, 2 * np.pi * r / L0)

return Field(a * b * c * d * e, grid)
return func ```
Example #21
 Source File: atmospheric_model.py    From hcipy with MIT License 5 votes
```def phase_structure_function_von_karman(r0, L0):
'''Return a Field generator for the phase structure function for Von Karman turbulence.

Parameters
----------
r0 : scalar
The Fried parameter.
L0 : scalar
The outer scale.

Returns
-------
Field generator
The phase structure Field generator.
'''
def func(grid):
r = grid.as_('polar').r + 1e-10

a = (L0 / r0)**(5 / 3)
b = 2**(1 / 6) * gamma(11 / 6) / np.pi**(8 / 3)
c = (24 / 5 * gamma(6 / 5))**(5 / 6)
d = gamma(5 / 6) / 2**(1 / 6)
e = (2 * np.pi * r / L0)**(5 / 6)
f = kv(5 / 6, 2 * np.pi * r / L0)

return Field(a * b * c * (d - e * f), grid)
return func ```
Example #22
 Source File: test_basic.py    From GraphicDesignPatternByPython with MIT License 5 votes
```def _check_kv(self):
cephes.kv(1,1) ```
Example #23
 Source File: test_basic.py    From GraphicDesignPatternByPython with MIT License 5 votes
```def test_k0(self):
ozk = special.k0(.1)
ozkr = special.kv(0,.1)
assert_almost_equal(ozk,ozkr,8) ```
Example #24
 Source File: test_basic.py    From GraphicDesignPatternByPython with MIT License 5 votes
```def test_k1(self):
o1k = special.k1(.1)
o1kr = special.kv(1,.1)
assert_almost_equal(o1k,o1kr,8) ```
Example #25
 Source File: test_basic.py    From GraphicDesignPatternByPython with MIT License 5 votes
```def test_negv_kv(self):
assert_equal(special.kv(3.0, 2.2), special.kv(-3.0, 2.2)) ```
Example #26
 Source File: test_basic.py    From GraphicDesignPatternByPython with MIT License 5 votes
```def test_kv0(self):
kv0 = special.kv(0,.2)
assert_almost_equal(kv0, 1.7527038555281462, 10) ```
Example #27
 Source File: test_basic.py    From GraphicDesignPatternByPython with MIT License 5 votes
```def test_kv2(self):
kv2 = special.kv(2,0.2)
assert_almost_equal(kv2, 49.51242928773287, 10) ```
Example #28
 Source File: test_basic.py    From GraphicDesignPatternByPython with MIT License 5 votes
```def test_kv_largearg(self):
assert_equal(special.kv(0, 1e19), 0) ```
Example #29
 Source File: test_basic.py    From GraphicDesignPatternByPython with MIT License 5 votes
```def test_kve(self):
kve1 = special.kve(0,.2)
kv1 = special.kv(0,.2)*exp(.2)
assert_almost_equal(kve1,kv1,8)
z = .2+1j
kve2 = special.kve(0,z)
kv2 = special.kv(0,z)*exp(z)
assert_almost_equal(kve2,kv2,8) ```
Example #30
 Source File: test_basic.py    From GraphicDesignPatternByPython with MIT License 5 votes
```def test_kvp_v0n1(self):
z = 2.2
assert_almost_equal(-special.kv(1,z), special.kvp(0,z, n=1), 10) ```