Let Pc be the associating projection from R^n onto C, C is
a nonempty closed convex subset of R^n, and Pc(x) is the
unique point in C with the property
|| x - Pc(x) || = min{ || x - z || : z ε C }.
Prove that if C is the closed unit ball,
C = { x ε R^n : || x || ≦ 1 }.
then the projection Pc is the radical map given by
Pc(x) = { x/(||x||) if ||x|| ≧ 1
x if ||x|| ≦ 1 }
請問這該怎麼做呢? 謝謝
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 118.168.166.75