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Mex and digraph in C++
graph, digraph and table are MATLAB objects (meaning they are implemented as .m files). There is no C++ syntax to access such ob...

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Decompose an N-dimensional array into outer products
Your last formula corresponds to the CP (canonical-polyadic) tensor decomposition. This is in a way the equivalent of the SVD fo...

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Can i adjust nodes in digraph?
You can't directly drag the nodes of a GraphPlot object. Indirectly, you can modify the XData, YData and ZData properties of the...

plus de 7 ans il y a | 4

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2 problem with minspantree.m in Matlab 2018a
The properties Underlying and EdgeProperties are private properties of the graph object, which can only be accessed in methods o...

plus de 7 ans il y a | 3

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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...

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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...

plus de 7 ans il y a | 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...

plus de 7 ans il y a | 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.

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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 ...

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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] =...

plus de 7 ans il y a | 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....

plus de 7 ans il y a | 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...

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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...

plus de 7 ans il y a | 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 ...

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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...

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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...

plus de 7 ans il y a | 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...

plus de 7 ans il y a | 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...

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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...

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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...

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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...

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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...

plus de 7 ans il y a | 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 ...

plus de 7 ans il y a | 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...

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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...

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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...

presque 8 ans il y a | 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...

presque 8 ans il y a | 0

presque 8 ans il y a | 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...

presque 8 ans il y a | 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...

presque 8 ans il y a | 1