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.
1,682 questions
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Mathematica running linear algebra unusually slow on the cluster
I’ve been running some Mathematica code on the HPC node and noticed that it’s running much slower than on my laptop — even for small calculations like multiplying two matrices. For example, something ...
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How to compute the complement of a subspace within another subspace?
I have two subspaces $V_1$, $V_2$ of $\mathbb{R}^n$ each specified as the span of a given list L1, L2 of basis vectors, and I ...
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Parameter search problem for satisfying an inequality
I am working with a $2 \times 2$ matrix
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How to implement a 2x2 operator in Mathematica?
I am trying to write a Mathematica program to compute the following:
For a given Hermitian matrix $\rho$, the operator $L_\theta$ with respect to a parameter $\theta$ is defined as:
\begin{equation}
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Plotting the surface gained by joining every point of a line to every point of another line in 3D space
How can I write code for displaying two lines in 3D space at random and connecting all points of line A with all points of line B and displaying the resulting surface in Mathematica (what would it's ...
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DSolve throws overdetermined error for large (but simple) system of ODEs
I have the following example, which is a proxy for the more complex problem I am trying to solve.(Apologies that the LaTeX is explicit, for some reason it trips the code formatting error on ...
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How to compute matrix LDU decomposition?
Use Mathematica to decompose a given matrix $Q$ as $LDU$, where $L$, $D$ is a triangular matrix, diagonal matrix, respectively, and $U$ is the transpose of $L$.
The built-in ...
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SemidefiniteOptimization function claiming no solution when a solution does exist
The following code
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Linear system of matrices
I don't know Mathematica very well, I have an equation involving matrices of the following form:
given two $5\times5$ matrices $A,B$ where $B$ is nilpotent we want to find a matrix $X$ such that
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Counting free variables in a system of linear equations
If we have a system of variables, say,
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Finding one non-negative solution to a system of linear equations
I need to find one non-negative solution to the system of linear equations
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Quantity dependent on choice of Eigenvectors of degenerate eigenvalues
This question uses the function sumFast (defined below as well) given : here.
Let us say we are given a matrix A and I want to ...
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Solving enormous linear systems [closed]
On an assigment on numerical analysis, i'm asked to solve some linear systems of order 200x200. However, neither the function LinearSolve nor the LU decomposition run in a reasonable amount of time. ...
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Legacy package: Making a linear map
I have downloaded a differential forms package from 1997. It can be found here. I am trying to understand how the code works. I am am having some difficulty, and am hoping that someone can help me out....
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The shortest path between two points in R^3 is a straight line. How can I find the coefficients for the equation of the line?
This is the system of equations; the points in R^3 are {x1,y1,z1} and {x2,y2,z2} and the coefficients are ...
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