…
►If either
or
is complex then (
22.2.6) gives the definition of
as a quotient of
theta functions.
…
►If either
or
is given, then we use
,
,
, and
, obtaining the values of the
theta functions as in §
20.14.
…
►Jacobi’s epsilon
function can be computed from its representation (
22.16.30) in terms of
theta functions and complete elliptic integrals; compare §
20.14.
…
§10.12 Generating Function and Associated Series
…
►Jacobi–Anger expansions: for
,
►
►
►
…
§22.21 Tables
…
►Lawden (1989, pp. 280–284 and 293–297) tabulates
,
,
,
,
to 5D for
,
, where
ranges from 1.
…
►Zhang and Jin (1996, p. 678) tabulates
,
,
for
and
to 7D.
…
►Tables of
theta functions (§
20.15) can also be used to compute the twelve Jacobian elliptic
functions by application of the quotient formulas given in §
22.2.
§20.14 Methods of Computation
►The Fourier series of §
20.2(i) usually converge rapidly because of the factors
or
, and provide a convenient way of calculating values of
.
…For instance, the first three terms of (
20.2.1) give the value of
(
) to 12 decimal places.
…
►For instance, to find
we use (
20.7.32) with
,
.
…Hence the first term of the series (
20.2.3) for
suffices for most purposes.
…