Definition
A real valued function f : X → R defined on a convex set X in a vector space is called convex if, for any two points and in X and any ,
The function is called strictly convex if
for every, and .
A function f is said to be (strictly) concave if −f is (strictly) convex.
Read more about this topic: Convex Function
Famous quotes containing the word definition:
“The physicians say, they are not materialists; but they are:MSpirit is matter reduced to an extreme thinness: O so thin!—But the definition of spiritual should be, that which is its own evidence. What notions do they attach to love! what to religion! One would not willingly pronounce these words in their hearing, and give them the occasion to profane them.”
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