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How to customize arrow of directed graph (digraph)
Since R2018b, there is a property ArrowPosition which allows the arrowhead to move around along the edge. There is no way of ch...

etwa 7 Jahre vor | 1

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how to plot graph without intersection?
It sounds like you are looking for functionality related to planar graphs. MATLAB does not have any methods specific to this, bu...

etwa 7 Jahre vor | 0

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How to work with quite large matrices?
The matrices A\B and A\C are very likely to be dense, even if A, B, C are sparse matrices. Since these are of size 400'000, no m...

etwa 7 Jahre vor | 2

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What is the best method to solve large linear system equation (Ax=b) (A:million~ by million~)
You can try one of the Iterative Methods and Preconditioners.

etwa 7 Jahre vor | 0

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How many arithmetic operations does matlab require to determine the Schur decomposition?
The second step in computing the Schur decomposition is the QR algorithm, not the QR decomposition (unfortunately the names are ...

etwa 7 Jahre vor | 0

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Get non-zero eigenvalues and eigenvectors
You could just remove the zero eigenvalues after computing them: >> X = [1 1; 1 1] X = 1 1 1 1 >> [V,l] =...

mehr als 7 Jahre vor | 0

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How I can construct Auxiliary matrix in graph for network topology to calculate shortest path between nodes has altitude and latitude ?
Have you looked at the graph and digraph classes in MATLAB (<https://www.mathworks.com/help/matlab/graph-and-network-algorithms....

mehr als 7 Jahre vor | 0

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Is it possible to vectorize this?
There is no general way to vectorize this. If the starts and ends vector define intervals that are not overlapping, and that cov...

mehr als 7 Jahre vor | 0

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Which algorithm does MATLAB eig() use to diagonalize a complex symmetric matrix?
EIG uses LAPACK functions for all cases. If there is a special case treatment for complex symmetric, I'm not aware of this. U...

mehr als 7 Jahre vor | 1

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Why I got different condition numbers for a simply matrix by two ways in Matlab?
The matrix H is not symmetric. The ratio of largest eigenvalue to smallest eigenvalue for the condition number is only true for ...

mehr als 7 Jahre vor | 2

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Eigs Function on Function Handle Not Converged
Hi Sam, The most likely reason for the convergence problems is that the eigenvalues are close together (or even multiples). T...

mehr als 7 Jahre vor | 1

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'Unexpected output' error using SVDS with function handle
Maybe the problem is that you use both |x| and |X| in the definition of the anonymous function? A matrix |X| in your workspace w...

mehr als 7 Jahre vor | 0

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Any alternates function to replace "eig"
The command eig(A,eye(15),'qz'); solves the eigenvalue problem A*x = lambda*x, but makes EIG treat it as the generalized...

mehr als 7 Jahre vor | 0

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Matrix similarity transformations introduce small imaginary eigenvalue components
If you know the matrix A is supposed to be symmetric, I'd say symmetrize A, and then symmetrize B again, because |Q*A*Q'| will i...

mehr als 7 Jahre vor | 0

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How can I do a real asymmetric eigen-decomposition in Matlab
Unfortunately, MATLAB doesn't have a function that does this, and I'm not aware of any existing implementations. To implement...

mehr als 7 Jahre vor | 1

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What should be used to diagonalise a complex sparse matrix instead of 'eig'?
If converting the sparse matrix into a dense matrix is possible, that seems like the best thing to do. How do you measure that t...

mehr als 7 Jahre vor | 0

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What is the complexity of Matlab's implementation of SVD?
The computational complexity of svd is O(max(m, n) * min(m, n)^2). If the 'econ' flag is not used and all three matrices are ret...

mehr als 7 Jahre vor | 1

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Eigenvectors are not orthogonal for some skew-symmetric matrices, why?
Since, as Lorenzo points out in a comment above, |1i*A| is hermitian, you could apply |eig| to that matrix: >> [U, D] = eig...

mehr als 7 Jahre vor | 0

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L2 norm or Frobenius norm?
The L2-norm of a matrix, |||A|||_2, ( |norm(A, 2)| in MATLAB) is an *operator norm*, which is computed as |max(svd(A))|. For ...

mehr als 7 Jahre vor | 6

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how to build many sparse matrices
The |sparse| function will often be faster if the second input, |col|, is sorted in ascending order. If you can cheaply construc...

mehr als 7 Jahre vor | 0

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Formulating objective function & constrain such that the eigenvalue is always positive
Hi Hammed, Your problem looks like a smooth nonlinear optimization problem: I believe the smallest eigenvalue of a linear com...

mehr als 7 Jahre vor | 1

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Specify a tolerance for backslash operation or linsolve while A is non-square? (QR solve)
Hi Sam, If you compute |A\B| for two large, sparse matrices (as you mention in your comment to John), the result will typical...

mehr als 7 Jahre vor | 2

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eigen value problem for sparse matrices
There aren't any practical algorithms for computing eigenvalues one by one. You can compute a subset of eigenvalues around a giv...

mehr als 7 Jahre vor | 0

mehr als 7 Jahre vor | 0

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eigen value problem for sparse matrices
The problem is that the eigenvectors of a sparse matrix are dense (in all practically relevant cases), so to store them would re...

mehr als 7 Jahre vor | 1

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Out of memory issue although there is more RAM space than matlab requires
Hi Oguzhan, As I remember from your <https://www.mathworks.com/matlabcentral/answers/414832-singular-value-decomposition-of-a...

mehr als 7 Jahre vor | 1

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Get in Order respond when using "eig" command
To sort the eigenvalues to be increasing in magnitude, use the following: [U, d] = eig(k, m, 'vector'); [d, ind] = sort(...

mehr als 7 Jahre vor | 1

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Singular Value Decomposition of a Large XYZ file
The way I thought of it was to use x and z as the 2d grid on which to interpolate, and y as the function value. Something like t...

mehr als 7 Jahre vor | 0

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eigs does not return the eigenvalues closest to shift sigma
Hi Olivier, I'm not sure I know much more to try out. Note that EIGS is doing Y = (A-SIGMA*I)\X based on the LU factorization...

mehr als 7 Jahre vor | 0

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Singular Value Decomposition of a Large XYZ file
First thing that occurs to me would be to interpolate the xyz data to lie on a rectangular grid in the x-z plane, and to then ap...

mehr als 7 Jahre vor | 0

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