§23.6 Relations to Other Functions
Contents
- §23.6(i) Theta Functions
- §23.6(ii) Jacobian Elliptic Functions
- §23.6(iii) General Elliptic Functions
- §23.6(iv) Elliptic Integrals
§23.6(i) Theta Functions
In this subsection
,
are any pair of
generators of the lattice
, and the lattice roots
,
,
are given by (23.3.9).
With
,
For further results for the
-function see
Lawden (1989, §6.2).
§23.6(ii) Jacobian Elliptic Functions
Again, in Equations (23.6.16)–(23.6.26),
are any pair of generators
of the lattice
and
are given by (23.3.9).
In (23.6.27)–(23.6.29) the modulus
is
given and
,
are the corresponding
complete elliptic integrals (§19.2(ii)). Also,
,
,
are the lattices with generators
,
,
, respectively.
Similar results for the other nine Jacobi functions can be constructed with the aid of the transformations given by Table 22.4.3.
For representations of the Jacobi functions
,
, and
as quotients of
-functions see
Lawden (1989, §§6.2, 6.3).
§23.6(iii) General Elliptic Functions
§23.6(iv) Elliptic Integrals
¶ Rectangular Lattice
Let
be on the perimeter of the rectangle with
vertices
.
Then
is real
(§§23.5(i)–23.5(ii)), and




For (23.6.30)–(23.6.35) and further identities see Lawden (1989, §6.12).
For relations to symmetric elliptic integrals see §19.25(vi).
¶ General Lattice
Let
be a point of
different from
, and define
by
where the integral is taken along any path from
to
that does not
pass through any of
. Then
,
where the value of
depends on the choice of path and determination of the
square root; see McKean and Moll (1999, pp. 87–88 and §2.5).

