dot-cor_lagr_askey function

Calculate Lagrangian correlation of the Askey form

Calculate Lagrangian correlation of the Askey form

.cor_lagr_askey(v1, v2, k = 2, h1, h2, u)

Arguments

  • v1: Prevailing wind, u-component.
  • v2: Prevailing wind, v-component.
  • k: Scale parameter of v\|\boldsymbol v\|, k>0k>0. Default is 2.
  • h1: Horizontal distance matrix or array.
  • h2: Vertical distance matrix or array, same dimension as h1.
  • u: Time lag, same dimension as h1.

Returns

Correlations of the same dimension as h1.

Details

The Lagrangian correlation function of the Askey form with parameters v=(v1,v2)R2\boldsymbol v = (v_1, v_2)^\top\in\mathbb{R}^2 has the form

C(h,u)=(11kvhuv)+3/2, C(\mathbf{h}, u)=\left(1-\dfrac{1}{k\|\boldsymbol v\|}\left\|\mathbf{h}-u\boldsymbol v\right\|\right)^{3/2}_+,

where \|\cdot\| is the Euclidean distance, c("x+=max(x,0),\nx_+=\\max(x,0),\n", "\\mathbf{h} = (\\mathrm{h}_1, \\mathrm{h}_2)^\\top\\in\\mathbb{R}^2"), and k>0k > 0 is the scale parameter controlling the magnitude of asymmetry in correlation.

References

Askey, R. (1973). Radial characteristic functions, Tech. Report No. 1262, Math. Research Center, University of Wisconsin-Madison.