[線代] Pseudoinverse of a Matrix

看板Math作者 (黑色魔影)時間11年前 (2013/01/04 20:47), 編輯推噓2(200)
留言2則, 2人參與, 最新討論串1/1
我想要問下面這個定理該怎麼證 給我一點trick也好 定理出自Friedberg 寫的Linear Algebra 第415頁 Thm6.29(證這個) Let A be an m x n matrix of rank r with a singular value decomposition A = UΣV* and nonzero singular values σ1≧σ2≧....≧σr + Let Σ be the n x m matrix defined by + Σij= 1/σi if i=k≦r 0 otherwise + + + Then A = VΣ U* and this is a singular value decomposition of A 參考定理:Thm6.27(這個不用證) Let A be an m x n matrix of rank r with a singular value decomposition A = UΣV* and positive singular values σ1≧σ2≧....≧σr Let Σ be the m x n matrix defined by Σij= σi if i=k≦r 0 otherwise Then exists an m x m unitary matrix U and an n x n unitary matrix V such that A = UΣV* 謝謝!! -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 114.43.161.74

01/04 21:38, , 1F
直接相乘?
01/04 21:38, 1F

01/05 01:55, , 2F
直接乘得到A^+A=I 別忘了U和V是unitary
01/05 01:55, 2F
文章代碼(AID): #1GvizKI4 (Math)