d-contracting: Robust against noise
- Function G is called "versatilely d-contracting in norm" if G() is invertible in the sense that, for any arbitrary given value of S ? {0,1}ns and any arbitrary X ? ?ns, it is not computationally difficult to find at least one value of W ? ?ns that satisfies the condition that G(W,X) = G(W,X+dx) = S for any small | dx | ? d.