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Zach Teitler
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Assume 2 n x ntwo $n \times n$ matrices A$A$ and B$B$ are known before hand and any precomputation can be done on them. Is there an efficient way to solve a set of linear problems: (A+w1 B) x1 = y1, (A+w2 B) x2 = y2, ...$$ \begin{split} (A+w_1 B) x_1 &= y_1, \\ (A+w_2 B) x_2 &= y_2, \\ &\vdots \end{split} $$ where w1, w2, ...$w_1, w_2, \dotsc$ are diagonal matrices (weights of a set of constraints), x1, x2, ...$x_1, x_2, \dotsc$ are unknown vectors and y1, y2, ...$y_1, y_2, \dotsc$ are right hand side vectors.

If w1 = w2 = ... = w$w_1 = w_2 = \dotsb = w$, then we can LU decompose (A+w B)$A+w B$ and simply solve for all (x, y) pairs$x_i$. Now the problem is that w1, w2, ...$w_1, w_2, \dotsc$ are different. So do I have to solve each problem individually or is there a more efficient way?

Assume 2 n x n matrices A and B are known before hand and any precomputation can be done on them. Is there an efficient way to solve a set of linear problems: (A+w1 B) x1 = y1, (A+w2 B) x2 = y2, ... where w1, w2, ... are diagonal matrices (weights of a set of constraints), x1, x2, ... are unknown vectors and y1, y2, ... are right hand side vectors.

If w1 = w2 = ... = w, then we can LU decompose (A+w B) and simply solve for all (x, y) pairs. Now the problem is that w1, w2, ... are different. So do I have to solve each problem individually or is there a more efficient way?

Assume two $n \times n$ matrices $A$ and $B$ are known before hand and any precomputation can be done on them. Is there an efficient way to solve a set of linear problems: $$ \begin{split} (A+w_1 B) x_1 &= y_1, \\ (A+w_2 B) x_2 &= y_2, \\ &\vdots \end{split} $$ where $w_1, w_2, \dotsc$ are diagonal matrices (weights of a set of constraints), $x_1, x_2, \dotsc$ are unknown vectors and $y_1, y_2, \dotsc$ are right hand side vectors.

If $w_1 = w_2 = \dotsb = w$, then we can LU decompose $A+w B$ and simply solve for all $x_i$. Now the problem is that $w_1, w_2, \dotsc$ are different. So do I have to solve each problem individually or is there a more efficient way?

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Efficient Matrix Precomputation

Assume 2 n x n matrices A and B are known before hand and any precomputation can be done on them. Is there an efficient way to solve a set of linear problems: (A+w1 B) x1 = y1, (A+w2 B) x2 = y2, ... where w1, w2, ... are diagonal matrices (weights of a set of constraints), x1, x2, ... are unknown vectors and y1, y2, ... are right hand side vectors.

If w1 = w2 = ... = w, then we can LU decompose (A+w B) and simply solve for all (x, y) pairs. Now the problem is that w1, w2, ... are different. So do I have to solve each problem individually or is there a more efficient way?