# Questions tagged [linear-algebra]

Questions about Mathematica functionality related to manipulating vector spaces and linear mappings between such spaces. This includes determination of matrix properties, matrix transformations, decompositions, and factoring.

1,441 questions
Filter by
Sorted by
Tagged with
37 views

1 vote
51 views

### Controlling accuracy for code

So I have a lot of trouble controlling precision and or accuracy with Mathematica. I have tried reading up for it but in the end I get even more confused. Here is my code, it is a little long but it ...
1 vote
76 views

### How can I generate a tridiagonal block matrix? [duplicate]

$$\begin{pmatrix}C&D&&&&\\D&C&D&&&\\&\ddots&\ddots&\ddots&&\\&&&D&C&D\\&&&&D&C\end{pmatrix}$$ I want ...
32 views

### Generate a random matrix with a condition on its eigenvalues

I can generate Radom matrices using mat = RandomReal[{-1, 1}, {2, 2}]; But how can I generate the mat matrix so that the ...
1 vote
43 views

### Solving a badly conditioned set of linear equations

I have a numerical high-precision badly conditioned over-constrained set of linear equations that I want to solve. I start out with m=616 equations and ...
341 views

### Is it possible to use the DGEEV and DSYEV LAPACK subroutines in Mathematica?

Here is my problem: I'm diagonalizing some matrices using Eigensystem[] to obtain eigenvalues and eigenvectors and I'm diagonalizing the same matrices using a ...
39 views

### Detailed properties of FindInstance

Does anybody know where to read about how FindInstance works? Specifically I want to use it in such a way that when it returns {}...
64 views

### Matrix basis using Orthogonalize

I have four matrices, ...
60 views

### Eigenvalues aren't given to be imaginary

So I have this matrix I am working with that looks like $$S=\begin{pmatrix}0 & -a & b\\ a & 0 & -c\\ -b & c& 0 \end{pmatrix}$$ and upon asking mathematica for the eigenvalues ...
1 vote
72 views

### How to get a rational solution of the linear system efficiently?

I got a large linear system ...
105 views

### Algorithm for the resolvent of a matrix, and LUBackSubstitution

Suppose A is a complex n x n matrix where n is quite big, given as a numeric array. For many ...
75 views

### Check Eigenvalues and Eigenvectors are correct [closed]

I have a matrix: J = {{0, -λ (1 + φ)/τ}, {-(1 + φ)/τ, δ}}; And I compute the Eigenvalues and Eigenvectors as follows: ...
1 vote
83 views

### Inverse of a matrix with symbolic variables

I want to evaluate the inverse of the following colossal matrix ...
44 views

122 views

62 views

### Solving complicated linear system [closed]

I have this system and I would solve it with mathematica, I try with the instruction Solve but I have an error Please help me.
1 vote
29 views

### Solve the current equation with respect to one of the coefficients and substitute it into each equation of the system

Good day to all! In this question about recurrence relations, I had a simple case when the k + 1th variable is represented in terms of ...
I am a complete beginner to Mathematica. I am trying to solve the following equation: $\frac{d}{dt}\rho_t = -0.5* \eta* \Gamma[\rho_t]$, where $\Gamma[\rho_t]$ is a 4x4 matrix whose coefficients are ...