KleinInvariantJ
gives the Klein invariant modular elliptic function .
Details
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- Mathematical function, suitable for both symbolic and numerical manipulation.
- The argument
is the ratio of Weierstrass half‐periods
.
- KleinInvariantJ is given in terms of Weierstrass invariants by
.
is invariant under any combination of the modular transformations
and
.
- For certain special arguments, KleinInvariantJ automatically evaluates to exact values.
- KleinInvariantJ can be evaluated to arbitrary numerical precision.
- KleinInvariantJ can be used with CenteredInterval objects. »
- KleinInvariantJ automatically threads over lists.
Examples
open allclose allBasic Examples (4)
Scope (23)
Numerical Evaluation (5)
The precision of the output tracks the precision of the input:
Evaluate efficiently at high precision:
KleinInvariantJ can be used with CenteredInterval objects:
Compute average-case statistical intervals using Around:
Specific Values (2)
Visualization (2)
Plot the real part of KleinInvariantJ:
Function Properties (10)
Complex domain of KleinInvariantJ:
KleinInvariantJ is a periodic function:
KleinInvariantJ threads elementwise over lists:
KleinInvariantJ is an analytic function on its domain of definition:
It has no singularities or discontinuities there:
is neither nondecreasing nor nonincreasing:
KleinInvariantJ is not injective over the complexes:
is neither non-negative nor non-positive:
is neither convex nor concave:
TraditionalForm formatting:
Differentiation (2)
Series Expansions (2)
Find the Taylor expansion using Series:
Applications (7)
Some modular properties of KleinInvariantJ are automatically applied:
Verify a more complicated identity numerically:
Find values at quadratic irrationals:
KleinInvariantJ is a modular function. Make an ansatz for a modular equation:
Form an overdetermined system of equations and solve it:
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This is the modular equation of order 2:
Solution of the Chazy equation :
Plot the absolute value in the complex plane:
Plot the imaginary part in the complex plane:
Define the discriminant of the Weierstrass elliptic curve:
It can be computed as the ratio of a power of invariant and the discriminant:
Possible Issues (2)
Machine-precision input may be insufficient to give the correct answer:
With exact input, the answer is correct:
KleinInvariantJ remains unevaluated outside of its domain of analyticity:
Text
Wolfram Research (1996), KleinInvariantJ, Wolfram Language function, https://reference.wolfram.com/language/ref/KleinInvariantJ.html (updated 2021).
CMS
Wolfram Language. 1996. "KleinInvariantJ." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2021. https://reference.wolfram.com/language/ref/KleinInvariantJ.html.
APA
Wolfram Language. (1996). KleinInvariantJ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/KleinInvariantJ.html