qstack.mathutils.xyz_integrals_float

Cartesian integrals for spherical harmonics (float version).

qstack.mathutils.xyz_integrals_float.I23(n, m, k)[source]

Compute an auxiliary integral needed for the integral over the unit sphere.

Parameters:
  • n (int)

  • m (int)

  • k (int)

Returns:

The value of the integral.

Return type:

float

qstack.mathutils.xyz_integrals_float.trinomial(k1, k2, k3)[source]

Compute the trinomial coefficient (k1+k2+k3)! / (k1! * k2! * k3!).

Parameters:
  • k1 (int)

  • k2 (int)

  • k3 (int)

Returns:

The value of the trinomial coefficient.

Return type:

float

qstack.mathutils.xyz_integrals_float.xyz(n, m, k)[source]

Compute the integral of x^2k y^2n z^2m over a unit sphere.

Parameters:
  • n (int) – Half of power of y.

  • m (int) – Half of power of z.

  • k (int) – Half of power of x.

Note

The argument order does not matter.

Returns:

The value of the integral.

Return type:

float