It is assumed the data can be described by a power law, expressed either as Y or X dependent (referring to the second and first axis on a fatigue curve).
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@@ -96,11 +97,11 @@ E = Y_{\textrm{p}} - Y_{\textrm{d}}
Extract the data with a positive error. We are only interested in the positive difference, as these are an indication of the points below the mean line.