NevilleThetaN[z,m]
gives the Neville theta function
.
NevilleThetaN
NevilleThetaN[z,m]
gives the Neville theta function
.
Details
- Mathematical function, suitable for both symbolic and numerical manipulation.
-
- NevilleThetaN[z,m] is a meromorphic function of
and has a complicated branch cut structure in the complex
plane. - For certain special arguments, NevilleThetaN automatically evaluates to exact values.
- NevilleThetaN can be evaluated to arbitrary numerical precision.
- NevilleThetaN automatically threads over lists.
Examples
open all close allBasic Examples (3)
NevilleThetaN[2., 1 / 3]Plot over a subset of the reals::
Plot[NevilleThetaN[ x, 1 / 3], {x, -10, 10}]Plot over a subset of the complexes:
ComplexPlot3D[NevilleThetaN[z ^ 2, 1 / 2], {z, -2 - 2I, 2 + 2I}, PlotLegends -> Automatic]Scope (29)
Numerical Evaluation (6)
NevilleThetaN[Pi / 3., 0]NevilleThetaN[E, .7]N[NevilleThetaN[5 / 6, 1 / 3], 50]N[NevilleThetaN[3Pi, 7 / 11], 50]The precision of the output tracks the precision of the input:
NevilleThetaN[1.211111100011100001, 1 / 3]N[NevilleThetaN[2 + I, 5 - I]]Evaluate efficiently at high precision:
NevilleThetaN[2, 1 / 5`100]//TimingNevilleThetaN[2, 13`1000];//TimingCompute average-case statistical intervals using Around:
NevilleThetaN[Around[2, 0.01], 1 / 2]Compute the elementwise values of an array:
NevilleThetaN[π I / 3, {{0, 1}, {1, 0}}]Or compute the matrix NevilleThetaN function using MatrixFunction:
MatrixFunction[NevilleThetaN[π I / 3, #]&, {{0, 1}, {1, 0}}]Specific Values (3)
Values at corners of the fundamental cell:
Table[NevilleThetaN[u1 EllipticK[m] + u2 I EllipticK[1 - m], m], {u1, {0, 1}}, {u2, {0, 1}}]NevilleThetaN for special values of elliptic parameter:
NevilleThetaN[u, 0]NevilleThetaN[u, 1]Find the first positive maximum of NevilleThetaN[x,1/2]:
xmax = x /. FindRoot[D[NevilleThetaN[x, 1 / 2 ], x] == 0, {x, 2}]Plot[NevilleThetaN[x, 1 / 2 ], {x, -9, 9}, Epilog -> Style[Point[{xmax, NevilleThetaN[xmax, 1 / 2 ]}], PointSize[Large], Red]]Visualization (3)
Plot the NevilleThetaN functions for various values of the parameter:
Plot[{NevilleThetaN[x, -1 / 2], NevilleThetaN[x, 1 / 2], NevilleThetaN[x, 1 / 3]}, {x, -5, 5}]Plot NevilleThetaN as a function of its parameter
:
Plot[{NevilleThetaN[1, m], NevilleThetaN[2, m], NevilleThetaN[3, m]}, {m, -10, 5}, PlotRange -> Automatic]ComplexContourPlot[Re[NevilleThetaN[z, 1 / 2]], {z, -2 - 2I, 2 + 2I}, IconizedObject[«PlotOptions»]]ComplexContourPlot[Im[NevilleThetaN[z, 1 / 2]], {z, -2 - 2I, 2 + 2I}, IconizedObject[«PlotOptions»]]Function Properties (13)
The real domain of NevilleThetaN:
FunctionDomain[NevilleThetaN[x, 0], x]The complex domain of NevilleThetaN:
FunctionDomain[NevilleThetaN[z, 0], z, Complexes]FunctionRange[NevilleThetaN[x, 0], x, y]//QuietFunctionRange[NevilleThetaN[x, 1], x, y]//QuietNevilleThetaN is an even function:
NevilleThetaN[-x, 1] == NevilleThetaN[x, 1]NevilleThetaN vanishes at
:
NevilleThetaN[I EllipticK[1 - m], m]NevilleThetaN threads elementwise over lists:
NevilleThetaN[{1, 2, 3, 4, 5}, 0.3]
is an analytic function of
for
:
FunctionAnalytic[NevilleThetaN[x, m], x]
is neither non-decreasing nor non-increasing:
FunctionMonotonicity[Subscript[ϑ, n](x❘(1/3)), x]FunctionInjective[Subscript[ϑ, n](x❘(1/3)), x]Plot[{NevilleThetaN[x, 1 / 3], 1.08}, {x, -7, 7}]FunctionSurjective[Subscript[ϑ, n](x❘(1/3)), x]Plot[{Subscript[ϑ, n](x❘(1/3)), 1.3}, {x, -10, 10}]
is non-negative for noninteger m:
Table[FunctionSign[Subscript[ϑ, n](x❘(1/n)), x], {n, 4}]
has no singularities or discontinuities for noninteger m:
Table[FunctionSingularities[Subscript[ϑ, n](x❘(1/n)), x], {n, 4}]Table[FunctionDiscontinuities[Subscript[ϑ, n](x❘(1/n)), x], {n, 4}]
is convex only for
and otherwise it is neither convex nor concave:
Table[FunctionConvexity[Subscript[ϑ, n](x❘(1/n)), x], {n, 5}]TraditionalForm formatting:
NevilleThetaN[z, m]//TraditionalFormDifferentiation (2)
D[NevilleThetaN[u, m], u]D[NevilleThetaN[u, m], m]Table[D[NevilleThetaN[u, 1 / 3], {u, k}], {k, 1, 3}]//Simplify//TraditionalFormPlot the higher-order derivatives:
Plot[%, {u, -10, 10}, PlotLegends -> {"First Derivative", "Second Derivative", "Third Derivative"}]Series Expansions (2)
Find the Taylor expansion using Series:
Series[NevilleThetaN[x, m], {x, 1, 2}]Plots of the first three approximations around
:
terms = Normal@Table[Series[NevilleThetaN[x, 1 / 3], {x, 1, m}], {m, 1, 5, 2}]//N;
Plot[{NevilleThetaN[x, 1 / 3], terms}, {x, -5, 5}, MaxRecursion -> 1]The Taylor expansion for small elliptic parameter
:
Series[NevilleThetaN[x, m], {m, 0, 3}]Series[NevilleThetaN[x, m], {m, 1, 1}]Generalizations & Extensions (1)
NevilleThetaN can be applied to power series:
NevilleThetaN[Sin[z] + O[z] ^ 4, m]Applications (5)
Plot over the arguments' plane:
Plot3D[NevilleThetaN[x, m], {x, -3 / 2Pi, 3 / 2Pi}, {m, -1, 1}]Conformal map from a unit triangle to the unit disk:
w[z_] := With[{ζ = (z Gamma[(1/3)]^3/π 2^1 / 3 3^1 / 4 ), m = Sin[(π/12)]^2}, (2^1 / 3 (1 + Sqrt[3]) (NevilleThetaC[ζ, m] - NevilleThetaN[ζ, m])((-2 + Sqrt[3]) NevilleThetaC[ζ, m] - NevilleThetaN[ζ, m])) / (NevilleThetaC[ζ, m]^2 - 2 NevilleThetaC[ζ, m] NevilleThetaN[ζ, m] + NevilleThetaN[ζ, m]^2 + 2 3^1 / 4 NevilleThetaD[ζ, m] NevilleThetaS[ζ, m])]Show points before and after the map:
trianglePoints = Flatten[Table[α Table[N[#1 + j / 16(#2 - #1)], {j, 0, 16}]&@@@({{2, -1 + I Sqrt[3]}, {-1 + I Sqrt[3], -1 - I Sqrt[3]}, {-1 - I Sqrt[3], 2}} / (2Sqrt[3])), {α, 1 / 8, 1, 1 / 8}]];Row[{Graphics[Point[{Re[#], Im[#]}]& /@ trianglePoints, Frame -> True, ImageSize -> Small],
Graphics[Point[{Re[#], Im[#]}]& /@ (w /@ trianglePoints), Frame -> True, ImageSize -> Small]}, Spacer[20]]Uniformization of a Fermat cubic
:
{a[u_], b[u_]} = With[{m = (2 - Sqrt[3]) / 4}, {-1 + (4 3^1 / 4 NevilleThetaD[u, m] NevilleThetaS[u, m]) / ((NevilleThetaC[u, m] - NevilleThetaN[u, m])^2 + 2 3^1 / 4 NevilleThetaD[u, m] NevilleThetaS[u, m]), -(2^1 / 3 (NevilleThetaC[u, m] - NevilleThetaN[u, m]) ((-1 + Sqrt[3]) NevilleThetaC[u, m] + (1 + Sqrt[3]) NevilleThetaN[u, m])) / ((NevilleThetaC[u, m] - NevilleThetaN[u, m])^2 + 2 3^1 / 4 NevilleThetaD[u, m] NevilleThetaS[u, m])}];ListPlot[Table[{a[u], b[u]}, {u, -Pi, Pi, 0.1}], AspectRatio -> Automatic]Verify that points on the curve satisfy
:
Cases[%, Point[l__] :> Map[Total, l ^ 3], Infinity, 1]Current flow in a rectangular conducting sheet with voltage applied at a pair of opposite corners:
flow[m_] = NevilleThetaD[x, m] NevilleThetaD[y, 1 - m]NevilleThetaS[x, m] NevilleThetaS[y, 1 - m] / (NevilleThetaC[x, m] NevilleThetaC[y, 1 - m] NevilleThetaN[x, m] NevilleThetaN[y, 1 - m]);With[{m = 0.2},
ContourPlot[flow[m], {x, 0, EllipticK[m]}, {y, 0, EllipticK[1 - m]}, ContourShading -> ColorData[35, "ColorList"], Contours -> 48]]Parametrize a lemniscate by arc length:
lemniscate[s_] := With[{t = s Sqrt[2]}, {NevilleThetaC[t, (1/2)] NevilleThetaD[t, (1/2)], (NevilleThetaC[t, (1/2)] NevilleThetaS[t, (1/2)]/Sqrt[2])} / NevilleThetaN[t, (1/2)]^2]Show arc length and classical parametrizations:
r[θ_] := If[Cos[2θ] > 0, Sqrt[Cos[2θ]], 0];Row[{ParametricPlot[{r[θ]Cos[θ], r[θ]Sin[θ]}, {θ, -Pi, Pi}, ImageSize -> Small],
ParametricPlot[Evaluate[lemniscate[s]], {s, 0, (Gamma[(1/4)]^2/Sqrt[2 π])}, ImageSize -> Small]}, Spacer[20]]Properties & Relations (5)
Basic simplifications are automatically carried out:
NevilleThetaN[-z, m]NevilleThetaN[z + 2EllipticK[m], m]All Neville theta functions are a multiple of shifted NevilleThetaN:
NevilleThetaN[z + EllipticK[m], m]NevilleThetaN[z + I EllipticK[1 - m], m]NevilleThetaN[z + EllipticK[m] + I EllipticK[1 - m], m]//SimplifyUse FullSimplify for expressions containing Neville theta functions:
NevilleThetaN[z, m] == (NevilleThetaD[z, m]/JacobiDN[z, m])//FullSimplifyNumerically find a root of a transcendental equation:
FindRoot[NevilleThetaN[z, (1/3)]^3 + NevilleThetaN[z, (1/2)] + z == 3, {z, 2}]NevilleThetaN can be represented with related elliptic functions:
NevilleThetaN[z, m] == NevilleThetaD[z + EllipticK[m], m] / (1 - m) ^ 4 ^ (-1)//FullSimplify//FullSimplifyRelated Guides
Related Links
History
Introduced in 1996 (3.0)
Text
Wolfram Research (1996), NevilleThetaN, Wolfram Language function, https://reference.wolfram.com/language/ref/NevilleThetaN.html.
CMS
Wolfram Language. 1996. "NevilleThetaN." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/NevilleThetaN.html.
APA
Wolfram Language. (1996). NevilleThetaN. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/NevilleThetaN.html
BibTeX
@misc{reference.wolfram_2026_nevillethetan, author="Wolfram Research", title="{NevilleThetaN}", year="1996", howpublished="\url{https://reference.wolfram.com/language/ref/NevilleThetaN.html}", note=[Accessed: 13-June-2026]}
BibLaTeX
@online{reference.wolfram_2026_nevillethetan, organization={Wolfram Research}, title={NevilleThetaN}, year={1996}, url={https://reference.wolfram.com/language/ref/NevilleThetaN.html}, note=[Accessed: 13-June-2026]}