Stability of Rounded Off Inverses Under Iteration
نویسندگان
چکیده
Let / be a monotone and strictly convex (or concave) function on a real interval and let g be the inverse function. Let I(x) = x. For a real valued function and N a positive integer let (t>pf(x) denote the rounding of (x) to N significant figures. Let h = gff » fa, the composition of f^ and g^¡. It is shown that h » ft » Iff = h o h » h « Ifj, and that equality can fail for fewer iterations.
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