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22
Jacobian Elliptic Functions
Properties
22.6
Elementary Identities
22.8
Addition Theorems
§22.7
Landen Transformations
ⓘ
Permalink:
http://dlmf.nist.gov/22.7
See also:
Annotations for
Ch.22
Contents
§22.7(i)
Descending Landen Transformation
§22.7(ii)
Ascending Landen Transformation
§22.7(iii)
Generalized Landen Transformations
§22.7(i)
Descending Landen Transformation
ⓘ
Keywords:
Jacobian elliptic functions
,
Landen transformations
,
descending
Notes:
See
Lawden (
1989
, pp. 79–80)
,
Walker (
1996
, p. 148)
,
Whittaker and Watson (
1927
, pp. 507–508)
.
Referenced by:
§22.17(ii)
,
§22.20(iii)
Permalink:
http://dlmf.nist.gov/22.7.i
See also:
Annotations for
§22.7
and
Ch.22
With
22.7.1
k
1
=
1
−
k
′
1
+
k
′
,
ⓘ
Defines:
k
1
: change of variable (locally)
Symbols:
k
′
: complementary modulus
A&S Ref:
16.12.1
Referenced by:
§22.20(iii)
Permalink:
http://dlmf.nist.gov/22.7.E1
Encodings:
TeX
,
pMML
,
png
See also:
Annotations for
§22.7(i)
,
§22.7
and
Ch.22
22.7.2
sn
(
z
,
k
)
=
(
1
+
k
1
)
sn
(
z
/
(
1
+
k
1
)
,
k
1
)
1
+
k
1
sn
2
(
z
/
(
1
+
k
1
)
,
k
1
)
,
ⓘ
Symbols:
sn
(
z
,
k
)
: Jacobian elliptic function
,
z
: complex
,
k
: modulus
and
k
1
: change of variable
A&S Ref:
16.12.2
Referenced by:
§22.20(iii)
Permalink:
http://dlmf.nist.gov/22.7.E2
Encodings:
TeX
,
pMML
,
png
See also:
Annotations for
§22.7(i)
,
§22.7
and
Ch.22
22.7.3
cn
(
z
,
k
)
=
cn
(
z
/
(
1
+
k
1
)
,
k
1
)
dn
(
z
/
(
1
+
k
1
)
,
k
1
)
1
+
k
1
sn
2
(
z
/
(
1
+
k
1
)
,
k
1
)
,
ⓘ
Symbols:
cn
(
z
,
k
)
: Jacobian elliptic function
,
dn
(
z
,
k
)
: Jacobian elliptic function
,
sn
(
z
,
k
)
: Jacobian elliptic function
,
z
: complex
,
k
: modulus
and
k
1
: change of variable
A&S Ref:
16.12.3
Referenced by:
§22.20(iii)
Permalink:
http://dlmf.nist.gov/22.7.E3
Encodings:
TeX
,
pMML
,
png
See also:
Annotations for
§22.7(i)
,
§22.7
and
Ch.22
22.7.4
dn
(
z
,
k
)
=
dn
2
(
z
/
(
1
+
k
1
)
,
k
1
)
−
(
1
−
k
1
)
1
+
k
1
−
dn
2
(
z
/
(
1
+
k
1
)
,
k
1
)
.
ⓘ
Symbols:
dn
(
z
,
k
)
: Jacobian elliptic function
,
z
: complex
,
k
: modulus
and
k
1
: change of variable
A&S Ref:
16.12.4
Referenced by:
§22.20(iii)
Permalink:
http://dlmf.nist.gov/22.7.E4
Encodings:
TeX
,
pMML
,
png
See also:
Annotations for
§22.7(i)
,
§22.7
and
Ch.22
§22.7(ii)
Ascending Landen Transformation
ⓘ
Keywords:
Jacobian elliptic functions
,
Landen transformations
,
ascending
Notes:
See
Lawden (
1989
, pp. 79–80)
,
Walker (
1996
, p. 148)
,
Whittaker and Watson (
1927
, pp. 507–508)
.
Referenced by:
§22.17(ii)
,
§22.20(iii)
Permalink:
http://dlmf.nist.gov/22.7.ii
See also:
Annotations for
§22.7
and
Ch.22
With
22.7.5
k
2
=
2
k
1
+
k
,
k
2
′
=
1
−
k
1
+
k
,
ⓘ
Defines:
k
2
: change of variable (locally)
and
k
2
′
: change of variable (locally)
Symbols:
k
: modulus
A&S Ref:
16.14.1
Permalink:
http://dlmf.nist.gov/22.7.E5
Encodings:
TeX
,
TeX
,
pMML
,
pMML
,
png
,
png
See also:
Annotations for
§22.7(ii)
,
§22.7
and
Ch.22
22.7.6
sn
(
z
,
k
)
=
(
1
+
k
2
′
)
sn
(
z
/
(
1
+
k
2
′
)
,
k
2
)
cn
(
z
/
(
1
+
k
2
′
)
,
k
2
)
dn
(
z
/
(
1
+
k
2
′
)
,
k
2
)
,
ⓘ
Symbols:
cn
(
z
,
k
)
: Jacobian elliptic function
,
dn
(
z
,
k
)
: Jacobian elliptic function
,
sn
(
z
,
k
)
: Jacobian elliptic function
,
z
: complex
,
k
: modulus
,
k
2
: change of variable
and
k
2
′
: change of variable
A&S Ref:
16.14.2
Permalink:
http://dlmf.nist.gov/22.7.E6
Encodings:
TeX
,
pMML
,
png
See also:
Annotations for
§22.7(ii)
,
§22.7
and
Ch.22
22.7.7
cn
(
z
,
k
)
=
(
1
+
k
2
′
)
(
dn
2
(
z
/
(
1
+
k
2
′
)
,
k
2
)
−
k
2
′
)
k
2
2
dn
(
z
/
(
1
+
k
2
′
)
,
k
2
)
,
ⓘ
Symbols:
cn
(
z
,
k
)
: Jacobian elliptic function
,
dn
(
z
,
k
)
: Jacobian elliptic function
,
z
: complex
,
k
: modulus
,
k
2
: change of variable
and
k
2
′
: change of variable
A&S Ref:
16.14.3
Permalink:
http://dlmf.nist.gov/22.7.E7
Encodings:
TeX
,
pMML
,
png
See also:
Annotations for
§22.7(ii)
,
§22.7
and
Ch.22
22.7.8
dn
(
z
,
k
)
=
(
1
−
k
2
′
)
(
dn
2
(
z
/
(
1
+
k
2
′
)
,
k
2
)
+
k
2
′
)
k
2
2
dn
(
z
/
(
1
+
k
2
′
)
,
k
2
)
.
ⓘ
Symbols:
dn
(
z
,
k
)
: Jacobian elliptic function
,
z
: complex
,
k
: modulus
,
k
2
: change of variable
and
k
2
′
: change of variable
A&S Ref:
16.14.4
Permalink:
http://dlmf.nist.gov/22.7.E8
Encodings:
TeX
,
pMML
,
png
See also:
Annotations for
§22.7(ii)
,
§22.7
and
Ch.22
§22.7(iii)
Generalized Landen Transformations
ⓘ
Keywords:
Jacobian elliptic functions
,
Landen transformations
,
generalized
Permalink:
http://dlmf.nist.gov/22.7.iii
See also:
Annotations for
§22.7
and
Ch.22
See
Khare and Sukhatme (
2004
)
.