curvature versus slope
  n = 22192 
  X=0, Y = 16.01 +/- 11.79 
  Weighted least-squares fit:  Y = 25.4 + 3.664 X  + -0.03952 X**2 

slope versus dZ, curvature < 5
  n = 7996 
  X=0, Y = 11.33 +/- 5.82 
  Weighted least-squares fit:  Y = 14.7 + -0.172 X  + 0.00478 X**2 
     at X = 100, Y = 45.2 
     effective RMSE xy = 67.2 

slope versus dZ, curvature < 15
  n = 14060 
  X=0, Y = 11.33 +/- 5.82 
  Weighted least-squares fit:  Y = 12.9 + 0.114 X  + 0.00079 X**2 

curvature versus dZ, slope < 10
  n = 5599 
  X=0, Y = 15.72 +/- 7.29 
  Weighted least-squares fit:  Y = 14.8 + 0.420 X  + 0.08798 X**2 


Number of samples 22238
Max dz = 900
Mean dz = 24
RMS dz = 110.602893271
100cm = 97.6346793776 percentile value of dz