A metric space (X,d) is monotone if there is a linear order < on X and a constant c>0 such that d(x,y)≦cd(x,z) for all x<y<z∈X. Properties of continuous functions with monotone graph (considered as a planar set) are investigated. It is shown, for example, that such a function can be almost nowhere differentiable, but must be differentiable at a dense set, and that the Hausdorff dimension of the graph of such a function is 1.
Key words and phrases
monotone metric space continuous function graph derivative approximate derivative absolutely continuous function σ-porous set
Mathematics Subject Classification
26A24 26A27 26A46
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