STAT 538 Lecture 1 Convex sets and functions
نویسنده
چکیده
i=2:k ti(xi−x1) and now t2:k can be any real numbers. Hence, the affine hull of x1:k is a subspace of dimension k− 1, spanned by xi − x1, i = 2 : k, and shifted from the origin by the shift x1. Exercise: Show that the result is the same no matter which xi we chose in place of x1. In particular, the affine hull of two points is the line that passes through them, the affine hull of three points is the plane that contains them, etc. • convex combination ∑
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