[Translation] calculate the uncertainties for res + krig

[KipCrossing]

Problem: As we combine layers, the uncertainty also need to be combined and carried through.

Solution: From here

We calculate the combined uncertainty. Once obtained we then convert it to a percent by dividing it by the combined value (res + krig).

Examples

In order to get paddocks with variation, we extended the paddock so that the kriging would be required to interpolate far from the points; hence having a higher uncertainty.

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available potassium
Min value: 262.26520031594157
Max value: 709.93932005769
RMSE: 133.69374447853525
Min uncertainties: 160.9562156555421
Max uncertainties: 276.079815994273
Min uncertainties %: 0.1235457353693329
Max uncertainties %: 0.5188469563506092
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cation exchange capacity
Min value: 13.76630177636314
Max value: 26.721666688330927
RMSE: 6.74274785971808
Min uncertainties: 9.058640565512476
Max uncertainties: 9.266553470912958
Min uncertainties %: 0.36334125091310376
Max uncertainties %: 0.7384675936723432
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