l3py.kernel

Isotropic harmonic integral kernels.

kernel.get_kernel(nmax)

Return kernel coefficients.

Parameters:

• kernel_name (string) – name of kernel, currently implemented: water height (‘ewh’, ‘water_height’), ocean bottom pressure (‘obp’, ‘ocean_bottom_pressure’)
• nmax (int) – maximum degree of kernel coefficients

Returns:

kernel – kernel associated with kernel_name

Return type:

Kernel subclass instance

Raises:

ValueError – if an unrecognized kernel name is passed

class l3py.kernel.GeoidHeight

Implementation of the geoid height kernel (disturbing potential divided by normal gravity).

Methods

kn(n[, r, colat])

Kernel coefficient for degree n.

kn(n, r=6378136.6, colat=0)

Kernel coefficient for degree n.

Parameters:

• n (int) – coefficient degree
• r (float, array_like shape (m,)) – radius of evaluation points
• colat (float, array_like shape (m,)) – co-latitude of evaluation points in radians

Returns:

kn – kernel coefficients for degree n for all evaluation points

Return type:

float, array_like shape (m,)

class l3py.kernel.Kernel

Base interface for spherical harmonic kernels.

Subclasses must implement a method kn which depends on degree radius and co-latitude and returns kernel coefficients.

Methods

kn

class l3py.kernel.OceanBottomPressure(nmax)

Implementation of the ocean bottom pressure kernel. Applied to a sequence of potential coefficients, the result is ocean bottom pressure in Pascal when propagated to space domain.

Parameters:nmax (int) – maximum spherical harmonic degree

Methods

kn(n[, r, colat])

Kernel coefficient for degree n.

kn(n, r=6378136.6, colat=0)

Kernel coefficient for degree n.

Parameters:

• n (int) – coefficient degree
• r (float, array_like shape (m,)) – radius of evaluation points
• colat (float, array_like shape (m,)) – co-latitude of evaluation points in radians

Returns:

kn – kernel coefficients for degree n for all evaluation points

Return type:

float, array_like shape (m,)

class l3py.kernel.Potential

Implementation of the Poisson kernel (disturbing potential).

Methods

kn(n[, r, colat])

Kernel coefficient for degree n.

kn(n, r=6378136.6, colat=0)

Kernel coefficient for degree n.

Parameters:

• n (int) – coefficient degree
• r (float, array_like shape (m,)) – radius of evaluation points
• colat (float, array_like shape (m,)) – co-latitude of evaluation points in radians

Returns:

kn – kernel coefficients for degree n for all evaluation points

Return type:

float, array_like shape (m,)

class l3py.kernel.WaterHeight(nmax, rho=1025)

Implementation of the water height kernel. Applied to a sequence of potential coefficients, the result is equivalent water height in meters when propagated to space domain.

Parameters:

• nmax (int) – maximum spherical harmonic degree
• rho (float) – density of water in [kg/m**3]

Methods

kn(n[, r, colat])

Kernel coefficient for degree n.

kn(n, r=6378136.6, colat=0)

Kernel coefficient for degree n.

Parameters:

• n (int) – coefficient degree
• r (float, array_like shape (m,)) – radius of evaluation points
• colat (float, array_like shape (m,)) – co-latitude of evaluation points in radians

Returns:

kn – kernel coefficients for degree n for all evaluation points

Return type:

float, array_like shape (m,)