ellippy.legendre.ellipke#

ellippy.legendre.ellipke(m)[source]#

Computes complete elliptic integrals of the first and second kind K(m) and E(m) simultaneously.

\[\mathrm{ellipke}(m) = \left(K(m),\, E(m)\right)\]
Parameters:

m (ArrayLike) – Elliptic parameter. m ∈ ℝ, m ≤ 1.

Returns:

A (K, E) pair of scalars or numpy.ndarray with the same shape as m.

Return type:

tuple[FloatArray, FloatArray] | tuple[float, float]

Raises:

ValueError – If m > 1 or inputs contain NaN.

Special Cases

  • ellipke(0) = (π/2, π/2)

  • ellipke(1) = (∞, 1)

  • ellipke(-∞) = (0, ∞)

Related Functions

  • K(m) = ellipk(m)

  • E(m) = ellipe(m)

Notes

  • This computes K(m) and E(m) simultaneously, which is faster than computing them separately.

  • The elliptic modulus k is frequently used instead of the parameter m, where k² = m.

References