A real function is $\Cal I$-density continuous if it is continuous with the $\Cal I$-density topology on both the domain and the range. If $f$ is analytic, then $f$ is $\Cal I$-density continuous. There exists a function which is both $C^\infty $ and convex which is not $\Cal I$-density continuous.
@article{118706, author = {Krzysztof Ciesielski and Lee Larson}, title = {Analytic functions are $\Cal I$-density continuous}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {35}, year = {1994}, pages = {645-652}, zbl = {0826.26011}, mrnumber = {1321235}, language = {en}, url = {http://dml.mathdoc.fr/item/118706} }
Ciesielski, Krzysztof; Larson, Lee. Analytic functions are $\Cal I$-density continuous. Commentationes Mathematicae Universitatis Carolinae, Tome 35 (1994) pp. 645-652. http://gdmltest.u-ga.fr/item/118706/
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