|WikiProject Mathematics||(Rated Start-class, Low-importance)|
Convex-analytic subgradient, then subdifferential, then generalizations.
In convex analysis, the subdifferential is the set of subgradients.
In nonsmooth analysis, Ioffe has stated that other subdifferentials reduce to the convex-analysis subdifferential for convex functions.
Subderivatives are primitive objects from which subdifferentials are constructed.
These statements suggest that the article should be entitled subgradient, not subderivative. It should first discuss the convex-analysis subdifferential and then generalizations (subderivatives of Dini, Frechet, etc.).16:57, 30 September 2011 (UTC)