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Subject: Solving Ax = B when some values of x are known From: Derrek Date: 11 Mar, 2012 07:11:26 Message: 1 of 6 
I am attempting to solve Ax = B where A is a 28,441 by 28,441 matrix, and B is a column vector with 28,441 known elements. I am trying to solve for x. However, I already know a few of the values of x. When I try to solve x= A\B I get numbers that are many orders of magnitude larger than they should be. In my case the maximum value found for x should be 300, but I am getting results up to 60,000. 
Subject: Solving Ax = B when some values of x are known From: Nasser M. Abbasi Date: 11 Mar, 2012 07:28:12 Message: 2 of 6 
On 3/11/2012 1:11 AM, Derrek wrote: 
Subject: Solving Ax = B when some values of x are known From: Derrek Date: 11 Mar, 2012 07:52:25 Message: 3 of 6 
Because the corresponding entries in A and B are several thousand in number, and they are spread throughout the matrix with no discernible pattern. The known values are not adjacent to each other. They are more or less randomly spread out. 
Subject: Solving Ax = B when some values of x are known From: Nasser M. Abbasi Date: 11 Mar, 2012 08:15:18 Message: 4 of 6 
On 3/11/2012 1:52 AM, Derrek wrote: 
Subject: Solving Ax = B when some values of x are known From: Bruno Luong Date: 11 Mar, 2012 08:45:14 Message: 5 of 6 
"Derrek " <derrek.igleheart682@topper.wku.edu> wrote in message <jjhj6t$kg2$1@newscl01ah.mathworks.com>... 
Subject: Solving Ax = B when some values of x are known From: Matt J Date: 11 Mar, 2012 15:19:13 Message: 6 of 6 
"Derrek " <derrek.igleheart682@topper.wku.edu> wrote in message <jjhljp$qvo$1@newscl01ah.mathworks.com>... 
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