def grad(f, dx, dy, dz, x=None, y=None, coordinate_system='cartesian'):
"""
Take the gradient of a pencil code scalar array f in various coordinate systems.
Keyword arguments:
*f*:
Pencil code scalar array f.
*dx, dy, dz*:
Grid spacing in the three dimensions.
*x, y*:
Radial (x) and polar (y) coordinates, 1d arrays.
*coordinate_system*:
Coordinate system under which to take the divergence.
Takes 'cartesian', 'cylindrical' and 'spherical'.
"""
import numpy as np
from pencil.math.derivatives.der import xder, yder, zder
if f.ndim != 3:
print("grad: must have scalar 3-D array f[mz, my, mx] for gradient.")
raise ValueError
grad_value = np.zeros((3, ) + f.shape)
if coordinate_system == 'cartesian':
grad_value[0] = xder(f, dx)
grad_value[1] = yder(f, dy)
grad_value[2] = zder(f, dz)
if coordinate_system == 'cylindrical':
if x is None:
print(
'ERROR: need to specify x (radius) for cylindrical coordinates.'
)
raise ValueError
# Make sure x has compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
grad_value[0] = xder(f, dx)
grad_value[1] = yder(f, dy) / x
grad_value[2] = zder(f, dz)
if coordinate_system == 'spherical':
if (x is None) or (y is None):
print(
'ERROR: need to specify x (radius) and y (polar angle) for spherical coordinates.'
)
raise ValueError
# Make sure x and y have compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
y = y[np.newaxis, :, np.newaxis]
grad_value[0] = xder(f, dx)
grad_value[1] = yder(f, dy) / x
grad_value[2] = zder(f, dz) / (x * np.sin(y))
return grad_value
def div(f, dx, dy, dz, x=None, y=None, coordinate_system="cartesian"):
"""
div(f, dx, dy, dz, x=None, y=None, coordinate_system="cartesian")
Take divervenge of pencil code vector array f in various coordinate systems.
Parameters
----------
f : ndarray
Pencil code vector array f.
dx, dy, dz : floats
Grid spacing in the three dimensions.
x, y : ndarrays
Radial (x) and polar (y) coordinates, 1d arrays.
coordinate_system : string
Coordinate system under which to take the divergence.
Takes 'cartesian', 'cylindrical' and 'spherical'.
"""
import numpy as np
from pencil.math.derivatives.der import xder, yder, zder
if f.ndim != 4:
print(
"div: must have vector 4-D array f[mvar, mz, my, mx] for divergence."
)
raise ValueError
if coordinate_system == "cartesian":
return xder(f[0], dx) + yder(f[1], dy) + zder(f[2], dz)
if coordinate_system == "cylindrical":
if x is None:
print(
"ERROR: need to specify x (radius) for cylindrical coordinates."
)
raise ValueError
# Make sure x has compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
return xder(x * f[0], dx) / x + yder(f[1], dy) / x + zder(f[2], dz)
if coordinate_system == "spherical":
if (x is None) or (y is None):
print(
"ERROR: need to specify x (radius) and y (polar angle) for spherical coordinates."
)
raise ValueError
# Make sure x and y have compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
y = y[np.newaxis, :, np.newaxis]
return (xder(x**2 * f[0], dx) / x**2 + yder(np.sin(y) * f[1], dy) /
(x * np.sin(y)) + zder(f[2], dz) / (x * np.sin(y)))
print("ERROR: could not recognize coordinate system {0}".format(
coordinate_system))
raise ValueError
def gij(f, dx, dy, dz, nder=6):
"""
Calculate del6 (defined here as d^6/dx^6 + d^6/dy^6 + d^6/dz^6, rather
than del2^3) of a scalar f for hyperdiffusion.
"""
import numpy as np
if f.ndim != 4 or f.shape[0] != 3:
print("curl3: must have vector 4-D array f[3, mz, my, mx] for curl3.")
raise ValueError
gij = np.array(f, f, f)
for i in range(3):
if nder == 1:
from pencil.math.derivatives.der import xder, yder, zder
gij[i, 0] = xder(f[i], dx, dy, dz)
gij[i, 1] = yder(f[i], dx, dy, dz)
gij[i, 2] = zder(f[i], dx, dy, dz)
elif nder == 2:
from pencil.math.derivatives.der import xder2, yder2, zder2
gij[i, 0] = xder2(f[i], dx, dy, dz)
gij[i, 1] = yder2(f[i], dx, dy, dz)
gij[i, 2] = zder2(f[i], dx, dy, dz)
elif nder == 3:
from pencil.math.derivatives.der import xder3, yder3, zder3
gij[i, 0] = xder3(f[i], dx, dy, dz)
gij[i, 1] = yder3(f[i], dx, dy, dz)
gij[i, 2] = zder3(f[i], dx, dy, dz)
elif nder == 4:
from pencil.math.derivatives.der import xder4, yder4, zder4
gij[i, 0] = xder4(f[i], dx, dy, dz)
gij[i, 1] = yder4(f[i], dx, dy, dz)
gij[i, 2] = zder4(f[i], dx, dy, dz)
elif nder == 5:
from pencil.math.derivatives.der import xder5, yder5, zder5
gij[i, 0] = xder5(f[i], dx, dy, dz)
gij[i, 1] = yder5(f[i], dx, dy, dz)
gij[i, 2] = zder5(f[i], dx, dy, dz)
elif nder == 6:
from pencil.math.derivatives.der import xder6, yder6, zder6
gij[i, 0] = xder6(f[i], dx, dy, dz)
gij[i, 1] = yder6(f[i], dx, dy, dz)
gij[i, 2] = zder6(f[i], dx, dy, dz)
return gij
def del2(f, dx, dy, dz, x=None, y=None, coordinate_system="cartesian"):
"""
del2(f, dx, dy, dz, x=None, y=None, coordinate_system="cartesian")
Calculate del2, the Laplacian of a scalar field f.
Parameters
----------
x, y : ndarrays
Radial (x) and polar (y) coordinates, 1d arrays.
run2D : bool
Deals with pure 2-D snapshots (solved the (x,z)-plane pb).
!Only for Cartesian grids at the moment!
coordinate_system : string
Coordinate system under which to take the divergence.
Takes 'cartesian', 'cylindrical' and 'spherical'.
"""
import numpy as np
from pencil.math.derivatives.der import xder2, yder2, zder2, xder, yder
if coordinate_system == "cartesian":
del2_value = xder2(f, dx) + yder2(f, dy) + zder2(f, dz)
if coordinate_system == "cylindrical":
if x is None:
print("ERROR: need to specify x (radius)")
raise ValueError
# Make sure x has compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
del2_value = (xder(f, dx) / x + xder2(f, dx) + yder2(f, dy) / (x**2) +
zder2(f, dz))
if coordinate_system == "spherical":
if x is None or y is None:
print("ERROR: need to specify x (radius) and y (polar angle)")
raise ValueError
# Make sure x and y have compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
y = y[np.newaxis, :, np.newaxis]
del2_value = (2 * xder(f, dx) / x + xder2(f, dx) +
np.cos(y) * yder(f, dy) / ((x**2) * np.sin(y)) +
yder2(f, dy) / (x**2) + zder2(f, dz) /
((x * np.sin(y))**2))
return del2_value
def curl3(f, dx, dy, dz, x=None, y=None, coordinate_system='cartesian'):
"""
Take the triple curl of a pencil code vector array f.
*x, y*:
Radial (x) and polar (y) coordinates, 1d arrays.
*run2D*:
Deals with pure 2-D snapshots (solved the (x,z)-plane pb).
!Only for Cartesian grids at the moment!
*coordinate_system*:
Coordinate system under which to take the divergence.
Takes 'cartesian' and 'cylindrical'.
"""
import numpy as np
from pencil.math.derivatives.der import xder, yder, zder, xder2, yder2, zder2, xder3, yder3, zder3
if (f.ndim != 4 or f.shape[0] != 3):
print("curl3: must have vector 4-D array f[3, mz, my, mx] for curl3.")
raise ValueError
curl3_value = np.zeros(f.shape)
if coordinate_system == 'cartesian':
curl3_value[0] = zder(xder2(f[1], dx) + yder2(f[1], dy), dz) + zder3(f[1], dz) - \
yder(xder2(f[2], dx) + zder2(f[2], dz), dy) - yder3(f[2], dy)
curl3_value[1] = xder3(f[2], dx) + xder(yder2(f[2], dy) + zder2(f[2], dz), dx) - \
zder(xder2(f[0], dx) + yder2(f[0], dy), dz) - zder3(f[0], dz)
curl3_value[2] = yder(xder2(f[0], dx) + zder2(f[0], dz), dy) + yder3(f[0], dy) - \
xder3(f[1], dx) - xder(yder2(f[1], dy) + zder2(f[1], dz), dx)
if coordinate_system == 'cylindrical':
if x is None:
print(
'ERROR: need to specify x (radius) for cylindrical coordinates.'
)
raise ValueError
# Make sure x has compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
curl3_value[0] = 2*yder(zder(f[0], dz), dy)/x**2 - yder(zder(f[2], dz), dy)/x**2 \
- xder2(yder(f[2], dy), dx)/x - yder3(f[2], dy)/x**3 \
+ yder2(zder(f[1], dz), dy)/x**2 - yder(zder2(f[2], dz), dy)/x \
+ zder3(f[1], dz) - zder(f[1], dz)/x**2 \
+ xder(zder(f[1], dz), dx)/x + xder2(zder(f[1], dz), dx)
curl3_value[1] = 2*yder(zder(f[1], dz), dy)/x**2 - yder2(zder(f[0], dz), dy)/x**2 \
- zder3(f[0], dz) + xder(zder2(f[2], dz), dx) \
- xder(zder(f[0], dz), dx)/x + zder(f[0], dz)/x**2 \
- xder2(zder(f[0], dz), dx) + xder(zder(f[2], dz), dx)/x \
- zder(f[2], dz)/x**2 + xder3(f[2], dx) \
+ xder(yder2(f[2], dy), dx)/x**2 - 2*yder2(f[2], dy)/x**3
curl3_value[2] = - xder(zder2(f[1], dz), dx) - zder2(f[1], dz)/x \
+ xder(f[1], dx) /x**2 - f[1]/x**3 \
- xder3(f[1], dx) + xder2(yder(f[0], dy), dx)/x \
- xder(yder(f[0], dy), dx)/x**2 + yder(f[0], dy)/x**3 \
- yder2(f[1], dy)/x**3 - xder(yder2(f[1], dy), dx)/x**2 \
+ yder3(f[0], dy)/x**3 + yder(zder2(f[0], dz), dy)/x \
-2*xder2(f[1], dx)/x
if coordinate_system == 'spherical':
if x is None or y is None:
print(
'ERROR: need to specify x (radius) and y (polar angle) for spherical coordinates'
)
raise ValueError
# Make sure x and y have compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
y = y[np.newaxis, :, np.newaxis]
# TODO: This one needs some fixing.
curl3_value[0] = (-1/x**3) * (np.sin(y)*((np.cos(y)**2 - 1)*(yder2(zder(f[1], dz), dy)) + \
(-np.cos(y)**2 * np.sin(y) + np.sin(y))*(yder3(f[2], dy)) \
-x**2 *(xder2(zder(f[1], dz), dx)) - zder3(f[1], dz) + \
np.sin(y)*(xder2(yder(f[2], dy), dx))*x**2 + (yder(zder2(f[2], dz), dy))*np.sin(y) \
+(-6*np.cos(y)**3 + 6* np.cos(y))*(yder2(f[2], dy))- 2*x*(xder(zder(f[1], dz), dx)) \
-3*np.sin(y)*np.cos(y)*(yder(zder(f[1], dz), dy)) + np.cos(y)*(xder2(f[2], dx))*x**2 + \
2*np.sin(y)*(xder(yder(f[2], dy), dx))*x + (zder2(f[2], dz))*np.cos(y) + \
(-2*np.cos(y)**2 + 1)*(zder(f[1], dz)) + (11*np.cos(y)**2 * np.sin(y) - 4*np.sin(y))*(yder(f[2], dy)) \
+ 2*np.cos(y)*(xder(f[2], dx))*x + (6*np.cos(y)**3 - 5*np.cos(y))*f[2]))
curl3_value[1] = 1/(x**3*np.sin(y)) * ((np.cos(y)**2 - 1)*(yder2(zder(f[0], dz), dy)) + \
(-x * np.cos(y)**2 + x)*np.sin(y)*(xder(yder2(f[2], dy), dx)) \
- (xder2(zder(f[0], dz), dx))*x**2 - zder3(f[0], dz) + x**3*(xder3(f[2], dx))*np.sin(y) + \
x*(xder(zder2(f[2], dz), dx))*np.sin(y) + (-2*np.cos(y)**2 + 2)*(yder(zder(f[1], dz), dy)) + \
3*x**2*xder2(f[2], dx)*np.sin(y) + zder2(f[2], dz)*np.sin(y) + (2*x*np.cos(y)**2 - x)*np.sin(y)*(xder(f[2], dx)) \
+ (3*np.cos(y)**3 - 3*np.cos(y))*(yder(f[2], dy)) + 2*np.sin(y)*np.cos(y)*(zder(f[1], dz)) + \
(-2*np.cos(y)**2 + 1)*np.sin(y)*f[2])
curl3_value[2] = 1/x**3 * ((yder3(f[0], dy))*(1-np.cos(y)**2) + (x*np.cos(y)**2 - x)*(xder(yder2(f[1], dy), dx)) + \
(xder2(yder(f[1], dy), dx))*x**2 + yder(zder2(f[0], dz), dy) - (xder3(f[1], dx))*x**3 - \
(xder(zder2(f[1], dz), dx))*x + (np.cos(y)**2 - 1)*(yder2(f[1], dy)) \
+ 3*(yder2(f[1], dy))*np.sin(y)*np.cos(y) - 3*(xder2(f[1], dx))*x**2 - \
3*(xder(yder(f[1], dy), dx))*np.sin(y)*np.cos(y)*x + zder2(f[1], dz) - \
2*(yder(zder(f[2], dz), dy))*np.sin(y) + (2*np.cos(y)**2 - 1)*(yder(f[1], dy)) + \
(-2*np.cos(y)**2 + x)*(xder(f[1], dx)) - 3*(yder(f[1], dy))*np.sin(y)*np.cos(y) - \
2*(zder(f[2], dz))*np.cos(y) + (-2*np.cos(y)**2 +1)*f[1])
return curl3_value
def del2v(f, dx, dy, dz, x=None, y=None, coordinate_system='cartesian'):
"""
Calculate del2, the Laplacian of a vector field f.
*x, y*:
Radial (x) and polar (y) coordinates, 1d arrays.
*run2D*:
Deals with pure 2-D snapshots (solved the (x,z)-plane pb).
!Only for Cartesian grids at the moment!
*coordinate_system*:
Coordinate system under which to take the divergence.
Takes 'cartesian', 'cylindrical' and 'spherical'.
"""
if f.shape[0] != 3:
print(
"Vector Laplacian: must have a vector 4D array f(3, mz, my, mx) for Vector Laplacian"
)
raise ValueError
import numpy as np
from pencil.math.derivatives.der import xder2, yder2, zder2, yder, zder
del2v_value = np.zeros(f.shape)
if coordinate_system == 'cartesian':
del2v_value[0] = xder2(f[0], dx) + yder2(f[0], dy) + zder2(f[0], dz)
del2v_value[1] = xder2(f[1], dx) + yder2(f[1], dy) + zder2(f[1], dz)
del2v_value[2] = xder2(f[2], dx) + yder2(f[2], dy) + zder2(f[2], dz)
if coordinate_system == 'cylindrical':
if x is None:
print('Error: need to specify x (radius)')
raise ValueError
# Make sure x has compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
del2v_value[0] = del2(f[0], dx, dy, dz, x=x, y=y, coordinate_system='cylindrical') \
- f[0]/(x**2) - 2*yder(f[1], dy)/x**2
del2v_value[1] = del2(f[1], dx, dy, dz, x=x, y=y, coordinate_system='cylindrical') \
- f[1]/(x**2) + 2*yder(f[0], dy)/x**2
del2v_value[2] = del2(f[2],
dx,
dy,
dz,
x=x,
y=y,
coordinate_system='cylindrical')
if coordinate_system == 'spherical':
if x is None or y is None:
print('ERROR: need to specify x (radius) and y (polar angle)')
# Make sure x and y have compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
y = y[np.newaxis, :, np.newaxis]
del2v_value[0] = del2(f[0], dx, dy, dz, x=x, y=y, coordinate_system='spherical') \
- 2*f[0]/x**2 - 2*yder(f[1], dy)/x**2 - 2*np.cos(y)*f[1]/(x**2*np.sin(y)) - 2*zder(f[2], dz)/(x**2*np.sin(y))
del2v_value[1] = del2(f[1], dx, dy, dz, x=x, y=y, coordinate_system='spherical') \
- f[1]/(x*np.sin(y))**2 + 2*yder(f[0], dy)/(x**2) - (2*np.cos(y))*zder(f[2], dz)/(x*np.sin(y))**2
del2v_value[2] = del2(f[2], dx, dy, dz, x=x, y=y, coordinate_system='spherical') \
- f[2]/(x*np.sin(y))**2 + 2*zder(f[0], dz)/(np.sin(y)*x**2) - (2*np.cos(y))*zder(f[1], dz)/(x*np.sin(y))**2
return del2v_value
def curl2(f, dx, dy, dz, x=None, y=None, coordinate_system='cartesian'):
"""
Take the double curl of a pencil code vector array f.
*x, y*:
Radial (x) and polar (y) coordinates, 1d arrays.
*run2D*:
Deals with pure 2-D snapshots (solved the (x,z)-plane pb).
!Only for Cartesian grids at the moment!
*coordinate_system*:
Coordinate system under which to take the divergence.
Takes 'cartesian', 'cylindrical' and 'spherical'.
"""
import numpy as np
from pencil.math.derivatives.der import xder, yder, zder, xder2, yder2, zder2
if (f.ndim != 4 or f.shape[0] != 3):
print("curl2: must have vector 4-D array f[3, mz, my, mx] for curl2.")
raise ValueError
curl2_value = np.zeros(f.shape)
if coordinate_system == 'cartesian':
curl2_value[0] = xder(yder(f[1], dy) + zder(f[2], dz), dx) \
-yder2(f[0], dy) - zder2(f[0], dz)
curl2_value[1] = yder(xder(f[0], dx) + zder(f[2], dz), dy) \
-xder2(f[1], dx) - zder2(f[1], dz)
curl2_value[2] = zder(xder(f[0], dx) + yder(f[1], dy), dz) \
-xder2(f[2], dx) - yder2(f[2], dy)
if coordinate_system == 'cylindrical':
if x is None:
print(
'ERROR: need to specify x (radius) for cylindrical coordinates.'
)
raise ValueError
# Make sure x has compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
curl2_value[0] = yder(f[1], dy)/x**2 + xder(yder(f[1], dy), dx)/x \
- yder2(f[0], dy)/x**2 - zder2(f[0], dz) + xder(zder(f[2], dz), dx)
curl2_value[1] = yder(zder(f[2], dz), dy)/x - zder2(f[1], dz) + f[1]/x**2 \
- xder(f[1], dx)/x - xder2(f[1], dx) + xder(yder(f[0], dy), dx)/x \
- yder(f[0], dy)/x**2
curl2_value[2] = zder(f[0], dz)/x + xder(zder(f[0], dz), dx) - zder(f[2], dx)/x \
- xder2(f[2], dx) - yder2(f[2], dy)/x**2 + yder(zder(f[1], dz), dy)/x
if coordinate_system == 'spherical':
if x is None or y is None:
print(
'ERROR: need to specify x (radius) and y (polar angle) for spherical coordinates.'
)
raise ValueError
# Make sure x and y have compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
y = y[np.newaxis, :, np.newaxis]
curl2_value[0] = (yder(
np.sin(y) * (xder(x * f[1], dx) - yder(f[0], dy)) / x, dy) - zder(
(zder(f[0], dz) / np.sin(y) - xder(x * f[2], dx)) / x, dz)) / (
x * np.sin(y))
curl2_value[1] = (zder(
(yder(np.sin(y) * f[2], dy) - zder(f[1], dz)) /
(x * np.sin(y)), dz) / np.sin(y) - xder(
(xder(x * f[1], dx) - yder(f[0], dy)), dx)) / x
curl2_value[2] = (xder(
(zder(f[0], dz) / np.sin(y) - xder(x * f[2], dx)), dx) - yder(
(yder(np.sin(y) * f[2], dy) - zder(f[1], dz)) /
(x * np.sin(y)), dy)) / x
return curl2_value
def curl(f,
dx,
dy,
dz,
x=None,
y=None,
run2D=False,
coordinate_system='cartesian'):
"""
Take the curl of a pencil code vector array f in various coordinate systems.
Keyword arguments:
*f*:
Pencil code scalar array f.
*dx, dy, dz*:
Grid spacing in the three dimensions.
*x, y*:
Radial (x) and polar (y) coordinates, 1d arrays.
*run2D*:
Deals with pure 2-D snapshots (solved the (x,z)-plane pb).
!Only for Cartesian grids at the moment!
*coordinate_system*:
Coordinate system under which to take the divergence.
Takes 'cartesian', 'cylindrical' and 'spherical'.
!Does not work for 2d runs yet!
"""
import numpy as np
from pencil.math.derivatives.der import xder, yder, zder
if f.shape[0] != 3:
print("curl: must have vector 4-D array f[3, mz, my, mx] for curl.")
raise ValueError
curl_value = np.zeros_like(f)
if (dy != 0. and dz != 0.):
# 3-D case
if coordinate_system == 'cartesian':
curl_value[0] = yder(f[2], dy) - zder(f[1], dz)
curl_value[1] = zder(f[0], dz) - xder(f[2], dx)
curl_value[2] = xder(f[1], dx) - yder(f[0], dy)
if coordinate_system == 'cylindrical':
if x is None:
print(
'ERROR: need to specify x (radius) for cylindrical coordinates.'
)
raise ValueError
# Make sure x has compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
curl_value[0] = (1 / x) * yder(f[2], dy) - zder(f[1], dz)
curl_value[1] = zder(f[0], dz) - xder(f[2], dx)
curl_value[2] = (1 / x) * xder(x * f[1], dx) - (1 / x) * yder(
f[0], dy)
if coordinate_system == 'spherical':
if (x is None) or (y is None):
print(
'ERROR: need to specify x (radius) and y (polar angle) for spherical coordinates.'
)
raise ValueError
# Make sure x and y have compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
y = y[np.newaxis, :, np.newaxis]
curl_value[0] = (yder(np.sin(y) * f[2], dy) -
zder(f[1], dz)) / (x * np.sin(y))
curl_value[1] = (zder(f[0], dz) / np.sin(y) -
xder(x * f[2], dx)) / x
curl_value[2] = (xder(x * f[1], dx) - yder(f[0], dy)) / x
elif dy == 0.:
# 2-D case in the xz-plane
curl_value[0] = zder(f, dz, run2D)[0] - xder(f, dx)[2]
else:
# 2-D case in the xy-plane
curl_value[0] = xder(f, dx)[1] - yder(f, dy)[0]
return curl_value
def curl3(f, dx, dy, dz, x=None, y=None, coordinate_system="cartesian"):
"""
curl3(f, dx, dy, dz, x=None, y=None, coordinate_system="cartesian")
Take the triple curl of a pencil code vector array f.
Parameters
----------
x, y : ndarrays
Radial (x) and polar (y) coordinates, 1d arrays.
run2D : bool
Deals with pure 2-D snapshots (solved the (x,z)-plane pb).
!Only for Cartesian grids at the moment!
coordinate_system : string
Coordinate system under which to take the divergence.
Takes 'cartesian' and 'cylindrical'.
"""
import numpy as np
from pencil.math.derivatives.der import (
xder,
yder,
zder,
xder2,
yder2,
zder2,
xder3,
yder3,
zder3,
)
if f.ndim != 4 or f.shape[0] != 3:
print("curl3: must have vector 4-D array f[3, mz, my, mx] for curl3.")
raise ValueError
curl3_value = np.zeros(f.shape)
if coordinate_system == "cartesian":
curl3_value[0] = (zder(xder2(f[1], dx) + yder2(f[1], dy), dz) +
zder3(f[1], dz) -
yder(xder2(f[2], dx) + zder2(f[2], dz), dy) -
yder3(f[2], dy))
curl3_value[1] = (xder3(f[2], dx) +
xder(yder2(f[2], dy) + zder2(f[2], dz), dx) -
zder(xder2(f[0], dx) + yder2(f[0], dy), dz) -
zder3(f[0], dz))
curl3_value[2] = (yder(xder2(f[0], dx) + zder2(f[0], dz), dy) +
yder3(f[0], dy) - xder3(f[1], dx) -
xder(yder2(f[1], dy) + zder2(f[1], dz), dx))
if coordinate_system == "cylindrical":
if x is None:
print(
"ERROR: need to specify x (radius) for cylindrical coordinates."
)
raise ValueError
# Make sure x has compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
curl3_value[0] = (2 * yder(zder(f[0], dz), dy) / x**2 -
yder(zder(f[2], dz), dy) / x**2 -
xder2(yder(f[2], dy), dx) / x -
yder3(f[2], dy) / x**3 +
yder2(zder(f[1], dz), dy) / x**2 -
yder(zder2(f[2], dz), dy) / x + zder3(f[1], dz) -
zder(f[1], dz) / x**2 +
xder(zder(f[1], dz), dx) / x +
xder2(zder(f[1], dz), dx))
curl3_value[1] = (2 * yder(zder(f[1], dz), dy) / x**2 -
yder2(zder(f[0], dz), dy) / x**2 - zder3(f[0], dz) +
xder(zder2(f[2], dz), dx) -
xder(zder(f[0], dz), dx) / x +
zder(f[0], dz) / x**2 - xder2(zder(f[0], dz), dx) +
xder(zder(f[2], dz), dx) / x -
zder(f[2], dz) / x**2 + xder3(f[2], dx) +
xder(yder2(f[2], dy), dx) / x**2 -
2 * yder2(f[2], dy) / x**3)
curl3_value[2] = (-xder(zder2(f[1], dz), dx) - zder2(f[1], dz) / x +
xder(f[1], dx) / x**2 - f[1] / x**3 -
xder3(f[1], dx) + xder2(yder(f[0], dy), dx) / x -
xder(yder(f[0], dy), dx) / x**2 +
yder(f[0], dy) / x**3 - yder2(f[1], dy) / x**3 -
xder(yder2(f[1], dy), dx) / x**2 +
yder3(f[0], dy) / x**3 +
yder(zder2(f[0], dz), dy) / x -
2 * xder2(f[1], dx) / x)
if coordinate_system == "spherical":
if x is None or y is None:
print(
"ERROR: need to specify x (radius) and y (polar angle) for spherical coordinates"
)
raise ValueError
# Make sure x and y have compatible dimensions.
x = x[np.newaxis, np.newaxis, :]
y = y[np.newaxis, :, np.newaxis]
# TODO: This one needs some fixing.
curl3_value[0] = (-1 / x**3) * (np.sin(y) * (
(np.cos(y)**2 - 1) * (yder2(zder(f[1], dz), dy)) +
(-np.cos(y)**2 * np.sin(y) + np.sin(y)) *
(yder3(f[2], dy)) - x**2 *
(xder2(zder(f[1], dz), dx)) - zder3(f[1], dz) + np.sin(y) *
(xder2(yder(f[2], dy), dx)) * x**2 +
(yder(zder2(f[2], dz), dy)) * np.sin(y) +
(-6 * np.cos(y)**3 + 6 * np.cos(y)) * (yder2(f[2], dy)) - 2 * x *
(xder(zder(f[1], dz), dx)) - 3 * np.sin(y) * np.cos(y) *
(yder(zder(f[1], dz), dy)) + np.cos(y) *
(xder2(f[2], dx)) * x**2 + 2 * np.sin(y) *
(xder(yder(f[2], dy), dx)) * x + (zder2(f[2], dz)) * np.cos(y) +
(-2 * np.cos(y)**2 + 1) * (zder(f[1], dz)) +
(11 * np.cos(y)**2 * np.sin(y) - 4 * np.sin(y)) *
(yder(f[2], dy)) + 2 * np.cos(y) * (xder(f[2], dx)) * x +
(6 * np.cos(y)**3 - 5 * np.cos(y)) * f[2]))
curl3_value[1] = (1 / (x**3 * np.sin(y)) * (
(np.cos(y)**2 - 1) * (yder2(zder(f[0], dz), dy)) +
(-x * np.cos(y)**2 + x) * np.sin(y) * (xder(yder2(f[2], dy), dx)) -
(xder2(zder(f[0], dz), dx)) * x**2 - zder3(f[0], dz) + x**3 *
(xder3(f[2], dx)) * np.sin(y) + x *
(xder(zder2(f[2], dz), dx)) * np.sin(y) + (-2 * np.cos(y)**2 + 2) *
(yder(zder(f[1], dz), dy)) + 3 * x**2 * xder2(f[2], dx) * np.sin(y)
+ zder2(f[2], dz) * np.sin(y) +
(2 * x * np.cos(y)**2 - x) * np.sin(y) * (xder(f[2], dx)) +
(3 * np.cos(y)**3 - 3 * np.cos(y)) *
(yder(f[2], dy)) + 2 * np.sin(y) * np.cos(y) * (zder(f[1], dz)) +
(-2 * np.cos(y)**2 + 1) * np.sin(y) * f[2]))
curl3_value[2] = (1 / x**3 * (
(yder3(f[0], dy)) * (1 - np.cos(y)**2) + (x * np.cos(y)**2 - x) *
(xder(yder2(f[1], dy), dx)) +
(xder2(yder(f[1], dy), dx)) * x**2 + yder(zder2(f[0], dz), dy) -
(xder3(f[1], dx)) * x**3 - (xder(zder2(f[1], dz), dx)) * x +
(np.cos(y)**2 - 1) * (yder2(f[1], dy)) + 3 *
(yder2(f[1], dy)) * np.sin(y) * np.cos(y) - 3 *
(xder2(f[1], dx)) * x**2 - 3 *
(xder(yder(f[1], dy), dx)) * np.sin(y) * np.cos(y) * x +
zder2(f[1], dz) - 2 * (yder(zder(f[2], dz), dy)) * np.sin(y) +
(2 * np.cos(y)**2 - 1) * (yder(f[1], dy)) +
(-2 * np.cos(y)**2 + x) * (xder(f[1], dx)) - 3 *
(yder(f[1], dy)) * np.sin(y) * np.cos(y) - 2 *
(zder(f[2], dz)) * np.cos(y) + (-2 * np.cos(y)**2 + 1) * f[1]))
return curl3_value