Truncation error bounds for continued fractions are obtained in terms of general conditions which ensure that the approximants
form a simple sequence; i.e., that
, where c is a constant, independent of
and
. The method is based on establishing the existence of a nested sequence
of
... [Show full abstract] bounded, convex regions with the following two properties (a) for all and , and (b) the diameter of is bounded above by . Applications are considered for several classes of continued fraction expansions including the continued fractions of Gauss (hypergeometric functions), S-fractions, J-fractions and T-fractions.