curvature versus slope
  n = 90369 
  X=0, Y = 6.29 +/- 4.71 
  Weighted least-squares fit:  Y = 10.4 + 4.750 X  + -0.05353 X**2 

slope versus dZ, curvature < 5
  n = 63063 
  X=0, Y = 46.39 +/- 29.13 
  Weighted least-squares fit:  Y = 47.9 + -1.648 X  + 0.01588 X**2 
     at X = 100, Y = 41.9 
     Bad fit. P2 = 0
slope versus dZ, curvature < 15
  n = 74348 
  X=0, Y = 46.15 +/- 29.04 
  Weighted least-squares fit:  Y = 44.1 + -1.292 X  + 0.01286 X**2 

curvature versus dZ, slope < 10
  n = 60337 
  X=0, Y = 53.31 +/- 30.70 
  Weighted least-squares fit:  Y = 54.7 + -6.442 X  + 0.31274 X**2 


Number of samples 90740
Max dz = 600
Mean dz = 36
RMS dz = 48.4561657583
100cm = 98.8858276394 percentile value of dz