Forward-difference

For the forward-difference scheme

1. start with <math>n</math> being the lowest number bin of the range over which the structure function is to be evaluated (number of bins in range should equal or exceed <math>n_{\text{rmax}}</math>)
   1. start with <math>\delta = 1</math>
   2. compute the second order forward-difference structure function <math>D(n,\delta)</math> as the segment mean of the square of the velocity difference between the bin <math>n</math> and bin <math>n + \delta</math>:
      
      <math>D(n, \delta) = \Big\langle \big[v^\prime(n, t) - v^\prime(n+\delta,\ t)\big]^2 \Big\rangle</math>
      
      where the angled brackets indicate the mean across all <math>t</math> for the data segment yielding a velocity difference after the application of the Level 1 QC criteria
   3. increment <math>\delta</math> and repeat steps until <math>\delta = n_{\text{rmax}}</math> or <math>n + \delta</math> exceeds the last bin of the range over which the structure function is to be evaluated
2. increment <math>n</math> and repeat steps until <math>n + 1</math> is the last bin of the range over which the structure function is to be evaluated

See example forward-difference calculation for more detail regarding the calculation

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