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ZDD - [S] Student's t (Symmetric)


This is the Zero Distortion Density (ZDD) used in the GenHVL[S] models. This generalized normal's a1 center parameter is the width of the Student's t, the Gaussian SD at infinite a3. The a3 or nu parameter in the ZDD nomenclature adjusts the fourth moment or kurtosis of the peak. This ZDD has no asymmetry or skew adjustment.

This is also the ZDD used in the GenNLC[S] models. For the GenNLC[S] models, a0, a1, and a3 will be identical. The a2 width or second moment term will reflect a kinetic time constant. Please see the GenHVL and GenNLC equivalence topic for further details.

This model produces identical shapes as the Pearson VII model.

[S] ZDD

ZDD - [S]7.png

a0 = Area

a1 = Center

a2 = Width

a3= DOF or nu (1>a3>1000000, Gaussian nu=Infinity, Lorentzian nu=1)

v5_ZDD_[S].png

Built-In Peak Model

  Student (Statistical family)

User-Defined Peaks and View Functions

  Student(x,area,center,width,shape) Student's t Area
  Student_C(x,amplitude,center,width,s-nu) Student's t cumulative
  Student_CR(x,amplitude,center,width,s-nu) Student's t reverse cumulative



c:\1pf\v5 help\home.gif ZDD - [G] ZDD - [W]