,v1Trying to solve a linear equation matrix with a log of X1-X5 in the matrix. Not sure how to use the log value in simulate to get correct result.

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Greg Zozuls 2023-5-1

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编辑： Torsten 2023-5-1

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Torsten 2023-5-1

编辑：Torsten 2023-5-1

6 equations for 11 unknows ? Then 11 - 6 = 5 of the unknowns can usually be chosen arbitrarily. Is it this what you want ?

Greg Zozuls 2023-5-1

No that's not what I want. I need to figure out how to use the log function to all unknowns using the lsqminnorm function

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Matt J 2023-5-1

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编辑：Matt J 2023-5-1

Make the change of variables z(i)=log(X(i)). Then use lsqminnorm to solve the linear equations in v(i) and z(i). You can then extract solutions for X(i) by inverting the change of variables X(i)=exp(Z(i)).

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Torsten 2023-5-1

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编辑：Torsten 2023-5-1

在 MATLAB Online 中打开

A = [1 0 0 0 0 0.05 0 0 0 0 0;-1 1 0 0 0 0 0.05 0 0 0 0;0 -1 1 0 0 0 0 0.05 0 0 0;0 0 -1 1 0 0 0 0 0.05 0 0;0 0 0 -1 1 0 0 0 0 0.05 0;0 0 0 0 -1 0 0 0 0 0 0.05];
B = [2.903;0; 0; 0; 0; -1.398];
sol = lsqminnorm(A,B);
norm(sol)
ans = 13.2118
A*sol-B
ans = 6×1
1.0e-14 *

    0.0888
    0.0222
    0.0611
   -0.1277
   -0.0999
   -0.0666
sol(1:5) = exp(sol(1:5));
X = sol(1:5)
X = 5×1
   13.9824
   10.7962
    8.3858
    6.5482
    5.1374
nu = sol(6:11)
nu = 6×1
    5.3040
    5.1721
    5.0532
    4.9468
    4.8529
    4.7710