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MATLAB Central > MATLAB Newsreader > Solve Matrix Equation AX=XB, Clarification 

Subject: Solve Matrix Equation AX=XB, Clarification From: Jeremy Date: 17 Jul, 2013 18:01:29 Message: 1 of 10 
I'm doing a school project with a vector network analyzer and gathering data on four adapters which I'll call a,b,c,d. Each of these devices can be characterized with a 2x2 matrix, and when you multiply these matrices together you get a 2x2 matrix that characterizes these adapters hooked together. I am hooking the adapters up in the configurations acb and adb which gives the resultant 2x2 matrices that I'll call s and t. I know the characteristic matrices for c and d but not a and b, and it is my goal to solve for them. So the resulting equations look like the following: 
Subject: Solve Matrix Equation AX=XB, Clarification From: Steven_Lord Date: 17 Jul, 2013 21:50:19 Message: 2 of 10 

Subject: Solve Matrix Equation AX=XB, Clarification From: Jeremy Date: 18 Jul, 2013 00:00:15 Message: 3 of 10 
"Steven_Lord" <slord@mathworks.com> wrote in message <ks73is$e9o$1@newscl01ah.mathworks.com>... 
Subject: Solve Matrix Equation AX=XB, Clarification From: dpb Date: 18 Jul, 2013 00:49:28 Message: 4 of 10 
On 7/17/2013 7:00 PM, Jeremy wrote: 
Subject: Solve Matrix Equation AX=XB, Clarification From: Jeremy Date: 18 Jul, 2013 01:13:12 Message: 5 of 10 
dpb <none@non.net> wrote in message <ks7e22$rd1$1@speranza.aioe.org>... 
Subject: Solve Matrix Equation AX=XB, Clarification From: Jeremy Date: 18 Jul, 2013 16:50:13 Message: 6 of 10 
I found something that seems to be quite useful in this thread: 
Subject: Solve Matrix Equation AX=XB, Clarification From: Jeremy Date: 18 Jul, 2013 18:32:11 Message: 7 of 10 
According to a resource I found online (https://hec.unil.ch/docs/files/23/100/handout1.pdf): 
Subject: Solve Matrix Equation AX=XB, Clarification From: Bruno Luong Date: 19 Jul, 2013 04:47:07 Message: 8 of 10 
"Jeremy" wrote in message <ks9cbb$53n$1@newscl01ah.mathworks.com>... 
Subject: Solve Matrix Equation AX=XB, Clarification From: Jeremy Date: 19 Jul, 2013 15:48:10 Message: 9 of 10 
My problem was with the null function used. If you use [U,S,V] = svd(G) instead and take the last column of V as your answer then it works. I believe it has to do with small errors in my measurements. 
Subject: Solve Matrix Equation AX=XB, Clarification From: Bruno Luong Date: 19 Jul, 2013 18:10:14 Message: 10 of 10 
"Jeremy" wrote in message <ksbn3q$rtd$1@newscl01ah.mathworks.com>... 
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