represents a Hann–Poisson window function of x.
HannPoissonWindow[x,α]
uses the parameter α.
HannPoissonWindow
represents a Hann–Poisson window function of x.
HannPoissonWindow[x,α]
uses the parameter α.
Details
- HannPoissonWindow is a window function typically used in signal processing applications where data needs to be processed in short segments.
- Window functions have a smoothing effect by gradually tapering data values to zero at the ends of each segment.
- HannPoissonWindow[x,α] is equal to
. - HannPoissonWindow[x] is equivalent to HannPoissonWindow[x,1].
- HannPoissonWindow automatically threads over lists.
Examples
open all close allBasic Examples (3)
Shape of a 1D Hann–Poisson window:
Plot[HannPoissonWindow[x], {x, -1, 1}]Shape of a 2D Hann–Poisson window:
Plot3D[HannPoissonWindow[x]HannPoissonWindow[y], {x, -1, 1}, {y, -1, 1}, PlotRange -> All]Extract the continuous function representing the Hann–Poisson window:
FunctionExpand[HannPoissonWindow[x]]Parameterized Hann–Poisson window:
FunctionExpand[HannPoissonWindow[x, α]]Scope (6)
HannPoissonWindow[0.1]Shape of a 1D Hann–Poisson window using a specified parameter:
Plot[HannPoissonWindow[x, 1.5], {x, -1, 1}]Variation of the shape as a function of the parameter α:
Plot3D[HannPoissonWindow[x, α], {α, 0, 5}, {x, -1, 1}]Translated and dilated Hann–Poisson window:
Plot[HannPoissonWindow[(x - 1) / 2], {x, -1, 3}]2D Hann–Poisson window with a circular support:
Plot3D[HannPoissonWindow[Sqrt[x ^ 2 + y ^ 2]], {x, -1, 1}, {y, -1, 1}, PlotRange -> All, Exclusions -> None]Discrete Hann–Poisson window of length 15:
ListPlot[Array[HannPoissonWindow, 15, {-1 / 2, 1 / 2}], Filling -> Axis]Discrete 15×10 2D Hann–Poisson window:
ListPointPlot3D[Array[HannPoissonWindow[#1] HannPoissonWindow[#2]&, {15, 10}, {{-1 / 2, 1 / 2}}], Filling -> Axis, PlotRange -> All]Applications (3)
Create a moving average filter of length 21:
h = ConstantArray[1 / 21., 21]Taper the filter using a Hamming window:
w = Array[HannPoissonWindow[#, 0.1]&, Length[h], {-1 / 2, 1 / 2}];
fir = w h / Total[w h];Log-magnitude plot of the power spectra of the filters:
LogLinearPlot[Evaluate[20Log[10, Abs@ListFourierSequenceTransform[#, ω]]& /@ {h, fir}], {ω, 0.1, Pi}, GridLines -> Automatic]Use a window specification to calculate sample PowerSpectralDensity:
proc = ARMAProcess[1, {.5}, {.3}, 1];
data = RandomFunction[proc, {50}];spec = PowerSpectralDensity[data, w, HannPoissonWindow];Compare to spectral density calculated without a windowing function:
sd = PowerSpectralDensity[data, w];sd === specThe plot shows that window smooths the spectral density:
Plot[{sd, spec}, {w, -π, π}, PlotRange -> All, PlotLegends -> {"no window", "with window"}]Compare to the theoretical spectral density of the process:
Plot[{spec, Evaluate@PowerSpectralDensity[proc, w]}, {w, -π, π}, PlotLegends -> {"data", "process"}]Use a window specification for time series estimation:
data = RandomFunction[ARMAProcess[1, {.3}, {.4}, 1], {300}];Specify window for spectral estimator:
EstimatedProcess[data, ARMAProcess[1, 1], ProcessEstimator -> {"SpectralEstimator", "Window" -> HannPoissonWindow}]Properties & Relations (3)
HannPoissonWindow[x,0] is equivalent to a Hann window:
Simplify[FunctionExpand[HannPoissonWindow[x, 0]]] == Simplify[FunctionExpand[HannWindow[x]]]The area under the Hann–Poisson window:
area = Integrate[HannPoissonWindow[x], {x, -∞, ∞}]Normalize to create a window with unit area:
Plot[{HannPoissonWindow[x], HannPoissonWindow[x] / area}, {x, -1, 1}, PlotRange -> All]Fourier transform of the Hann–Poisson window:
f = FourierTransform[HannPoissonWindow[x], x, w]Power spectrum of the Hann–Poisson window:
LogLinearPlot[20 Log[10, Abs[f]], {w, .1, 80}]Possible Issues (1)
2D sampling of Hann–Poisson window will use a different parameter for each row of samples when passed as a symbol to Array:
Array[HannPoissonWindow, {30, 30}, {{-1 / 2, 1 / 2}}]//ListPlot3DArray[HannPoissonWindow[#1] HannPoissonWindow[#2]&, {30, 30}, {{-1 / 2, 1 / 2}}]//ListPlot3DRelated Guides
History
Text
Wolfram Research (2012), HannPoissonWindow, Wolfram Language function, https://reference.wolfram.com/language/ref/HannPoissonWindow.html.
CMS
Wolfram Language. 2012. "HannPoissonWindow." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/HannPoissonWindow.html.
APA
Wolfram Language. (2012). HannPoissonWindow. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/HannPoissonWindow.html
BibTeX
@misc{reference.wolfram_2026_hannpoissonwindow, author="Wolfram Research", title="{HannPoissonWindow}", year="2012", howpublished="\url{https://reference.wolfram.com/language/ref/HannPoissonWindow.html}", note=[Accessed: 12-June-2026]}
BibLaTeX
@online{reference.wolfram_2026_hannpoissonwindow, organization={Wolfram Research}, title={HannPoissonWindow}, year={2012}, url={https://reference.wolfram.com/language/ref/HannPoissonWindow.html}, note=[Accessed: 12-June-2026]}