[理工] [線代]-least squares相關問題

看板Grad-ProbAsk作者 (阿年:))時間14年前 (2010/03/11 16:30), 編輯推噓2(204)
留言6則, 2人參與, 最新討論串1/1
1.Find the least squares solution to each of the following systems. (a) x1 + x2 = 3 (b) (c) 2x1 - 3x2 = 1 BALABALA BALABALA 0x1 + 0x2 = 2 ^ 2.For each of your solutions x in Excercise 1 : ^ (a) Determine the projection p = Ax. ^ (b) Calculate the residual r(x). ^ (c) Verify that r(x) € N(A^T). 3.For each of the following systems Ax = b, find all least squaressolutions. ╭ ╮ ╭ ╮ │ 1 2 │ │3│ (a) A =│ 2 4 │, b =│2│ (b) BALABALA │-1 -2 │ │1│ ╰ ╯ ╰ ╯ 4.For each of the systems in Exercise 3, determine the projection p of b onto R(A) and verify that b-p is orthogonal to each of the column vectors of A. 嗯嗯…… 我第一題和第三題都會算, 可是第二和第四題我不懂它是要求什麼@@ 可以請大大講解順便示範一下嗎? 麻煩各位好心的大大了(鞠躬 -- Don't walk in front of me, I may not follow. Don't walk behind me, I may not lead. Walk beside me and be my friend. -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 120.127.32.231

03/11 17:17, , 1F
第2 (a)應該是問投影矩陣 然後(b)他問剩餘的向量是哪些
03/11 17:17, 1F

03/11 17:18, , 2F
N(A^T)=R(A)垂直 就是剩餘的向量 他要你證這個
03/11 17:18, 2F

03/11 17:20, , 3F
第四題要你算投影到A行空間的矩陣
03/11 17:20, 3F

03/11 17:22, , 4F
p是投影在A上 所以b-p垂直於A的行空間 大概是這樣
03/11 17:22, 4F

03/11 17:30, , 5F
少打 第四題要你算b投影到A的向量 就是p
03/11 17:30, 5F

03/11 21:13, , 6F
謝謝AI大,我再去研究看看(鞠躬
03/11 21:13, 6F
文章代碼(AID): #1BcAetTj (Grad-ProbAsk)