In this paper, we defined the fuzzy upper, fuzzy lower, and fuzzy boundary sets of a
rough fuzzy set λ in a fuzzy approximation space (X, R). Based on λ and R, we
introduced the fuzzy ideal approximation interior operator intlambdaR and the fuzzy
ideal approximation closure operator clR
λ. We joined the fuzzy ideal notion with the
fuzzy approximation spaces, and then introduced the fuzzy ideal approximation
closure and interior operators associated to a rough fuzzy set λ. Fuzzy ideal
approximation connectedness and the fuzzy ideal approximation continuity between
fuzzy ideal approximation spaces are introduced.