curvature versus slope
  n = 424763 
  X=0, Y = 28.47 +/- 23.99 
  Weighted least-squares fit:  Y = 59.9 + 1.612 X  + -0.01717 X**2 

slope versus dZ, curvature < 5
  n = 25622 
  X=0, Y = 116.76 +/- 5.77 
  Weighted least-squares fit:  Y = 106.9 + -0.083 X  + 0.00208 X**2 
     at X = 100, Y = 119.5 
     effective RMSE xy = 83.7 

slope versus dZ, curvature < 15
  n = 62058 
  X=0, Y = 117.58 +/- 5.00 
  Weighted least-squares fit:  Y = 106.6 + -0.117 X  + 0.00261 X**2 

curvature versus dZ, slope < 10
  n = 12061 
  X=0, Y = 109.00 +/- 9.96 
  Weighted least-squares fit:  Y = 109.3 + -1.741 X  + 0.02628 X**2 


Number of samples 425626
Max dz = 900
Mean dz = 113
RMS dz = 137.38267722
100cm = 45.9556042159 percentile value of dz