scipy.special.ellipkm1¶

scipy.special.
ellipkm1
(p) = <ufunc 'ellipkm1'>¶ Complete elliptic integral of the first kind around m = 1
This function is defined as
\[K(p) = \int_0^{\pi/2} [1  m \sin(t)^2]^{1/2} dt\]where m = 1  p.
 Parameters
 parray_like
Defines the parameter of the elliptic integral as m = 1  p.
 Returns
 Kndarray
Value of the elliptic integral.
See also
Notes
Wrapper for the Cephes [1] routine ellpk.
For p <= 1, computation uses the approximation,
\[K(p) \approx P(p)  \log(p) Q(p),\]where \(P\) and \(Q\) are tenthorder polynomials. The argument p is used internally rather than m so that the logarithmic singularity at m = 1 will be shifted to the origin; this preserves maximum accuracy. For p > 1, the identity
\[K(p) = K(1/p)/\sqrt(p)\]is used.
References
 1
Cephes Mathematical Functions Library, http://www.netlib.org/cephes/