WOLFRAM

SpheroidalS1[n,m,γ,z]

gives the radial spheroidal function of the first kind.

Details

  • Mathematical function, suitable for both symbolic and numerical manipulation.
  • The radial spheroidal functions satisfy the differential equation with the spheroidal eigenvalue given by SpheroidalEigenvalue[n,m,γ].
  • The are normalized according to the MeixnerSchäfke scheme.
  • SpheroidalS1 can be evaluated to arbitrary numerical precision.
  • SpheroidalS1 automatically threads over lists. »

Examples

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Basic Examples  (5)Summary of the most common use cases

Evaluate numerically:

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Plot over a subset of the reals:

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Plot over a subset of the complexes:

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Series expansion at the origin:

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Series expansion at a singular point:

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Scope  (21)Survey of the scope of standard use cases

Numerical Evaluation  (5)

Evaluate numerically:

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Evaluate to high precision:

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The precision of the output tracks the precision of the input:

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Complex number inputs:

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Evaluate efficiently at high precision:

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Compute the elementwise values of an array using automatic threading:

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Or compute the matrix SpheroidalS1 function using MatrixFunction:

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Specific Values  (4)

Simple exact values are generated automatically:

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Find the first positive maximum of SpheroidalS1[2,0,5,x]:

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SpheroidalS1 functions become elementary if m=1 and γ=n π/2 :

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TraditionalForm typesetting:

Visualization  (3)

Plot the SpheroidalS1 function for integer orders:

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Plot the SpheroidalS1 function for noninteger parameters:

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Plot the real part of TemplateBox[{2, 0, 1, z}, SpheroidalS1]:

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Plot the imaginary part of TemplateBox[{2, 0, 1, z}, SpheroidalS1]:

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Function Properties  (5)

SpheroidalS1 is not an analytic function:

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TemplateBox[{1, 2, {pi, /, 2}, x}, SpheroidalS1] has both singularities and discontinuities for :

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TemplateBox[{1, 2, {pi, /, 2}, x}, SpheroidalS1] is neither non-decreasing nor non-increasing:

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TemplateBox[{1, 2, {pi, /, 2}, x}, SpheroidalS1] is not injective:

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SpheroidalS1 is neither non-negative nor non-positive:

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SpheroidalS1 is neither convex nor concave:

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Differentiation  (2)

First derivative with respect to z:

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Higher derivatives with respect to z:

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Plot the higher derivatives with respect to z when n=10, m=2 and γ=1/3:

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Series Expansions  (2)

Find the Taylor expansion using Series:

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Plots of the first three approximations around :

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Taylor expansion at a generic point:

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Applications  (4)Sample problems that can be solved with this function

Spheroidal angular harmonics are eigenfunctions of the Sinc transform on the interval :

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Plot the eigenvalue:

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Find resonant frequencies for the Dirichlet problem in the prolate spheroidal cavity:

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Determine the first few frequencies:

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Plot the prolate and oblate functions:

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Build a near-spherical approximation to :

First few terms of the approximation:

Compare numerically:

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Possible Issues  (1)Common pitfalls and unexpected behavior

Spheroidal functions do not evaluate for half-integer values of n and generic values of m:

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Wolfram Research (2007), SpheroidalS1, Wolfram Language function, https://reference.wolfram.com/language/ref/SpheroidalS1.html.
Wolfram Research (2007), SpheroidalS1, Wolfram Language function, https://reference.wolfram.com/language/ref/SpheroidalS1.html.

Text

Wolfram Research (2007), SpheroidalS1, Wolfram Language function, https://reference.wolfram.com/language/ref/SpheroidalS1.html.

Wolfram Research (2007), SpheroidalS1, Wolfram Language function, https://reference.wolfram.com/language/ref/SpheroidalS1.html.

CMS

Wolfram Language. 2007. "SpheroidalS1." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/SpheroidalS1.html.

Wolfram Language. 2007. "SpheroidalS1." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/SpheroidalS1.html.

APA

Wolfram Language. (2007). SpheroidalS1. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/SpheroidalS1.html

Wolfram Language. (2007). SpheroidalS1. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/SpheroidalS1.html

BibTeX

@misc{reference.wolfram_2025_spheroidals1, author="Wolfram Research", title="{SpheroidalS1}", year="2007", howpublished="\url{https://reference.wolfram.com/language/ref/SpheroidalS1.html}", note=[Accessed: 16-April-2025 ]}

@misc{reference.wolfram_2025_spheroidals1, author="Wolfram Research", title="{SpheroidalS1}", year="2007", howpublished="\url{https://reference.wolfram.com/language/ref/SpheroidalS1.html}", note=[Accessed: 16-April-2025 ]}

BibLaTeX

@online{reference.wolfram_2025_spheroidals1, organization={Wolfram Research}, title={SpheroidalS1}, year={2007}, url={https://reference.wolfram.com/language/ref/SpheroidalS1.html}, note=[Accessed: 16-April-2025 ]}

@online{reference.wolfram_2025_spheroidals1, organization={Wolfram Research}, title={SpheroidalS1}, year={2007}, url={https://reference.wolfram.com/language/ref/SpheroidalS1.html}, note=[Accessed: 16-April-2025 ]}