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Last seen: 9 mois il y a Actif depuis 2015

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Matlab symbolic : calculate expression with vector of symbolic variables
have done some progress in investigation to compute the 2 variances : Now, I did : clear syms l_min l_max fsky ...

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Matlab symbolic : calculate expression with vector of symbolic variables
Hello, I need to calculate with Matlab symbolic the following expression : "l" is a vector of symbolic variables and...

environ un an il y a | 1 réponse | 0

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Solve a matricial equation, i.e a system of 16 equations with 16 unknown : Error when call solve function
I wonder under which conditions I could have equality between the 2 matrices 4x4. I build my 2 matrixes from which I would lik...

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Remove a line and column in a symbolic matrix and shift to -1 all the superior indices of names of variables into this symbolic matrix
**Update 1:** For the moment with a 5x5 symbolic array, I managed to print pattern like this : a=sym('a_',[5,5]) ...

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Remove a line and column in a symbolic matrix and shift to -1 all the superior indices of names of variables into this symbolic matrix
Update : For the moment with a 10x10 symbolic array, I tried (in a first decrease all the 2 indices from 1) : a=sym('a_',[10,1...

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Remove a line and column in a symbolic matrix and shift to -1 all the superior indices of names of variables into this symbolic matrix
I have a 32x32 symbolic matrix FISH_Big_18_SYM = sym('sp_', [32,32], 'positive'); After some computations...

plus d'un an il y a | 2 réponses | 0

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Looking for a matlab script that extracts data from a plot figure ( here 2D contours from Covariance matrix or Markov chains) and reproduce the original figure
@Joseph Cheng Thanks for your detailled answer. I realize there is a lot of work to do more to extract these covariance matrice...

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Looking for a matlab script that extracts data from a plot figure ( here 2D contours from Covariance matrix or Markov chains) and reproduce the original figure
I am looking for a script which is able for example to extract data from a 2D contours plot like below : I tried to apply...

plus d'un an il y a | 2 réponses | 0

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Large substitution from symbolic matrix to numerical values while keeping 4 unknowns into the new matrix
I have to solve the equality between 2 matrixes 12x12 containing a lot of symbolic variables and with which I perform inversion ...

presque 2 ans il y a | 1 réponse | 0

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MATLAB : find a way with GPU NVIDIA to inverse quickly a large matrix of symbolic variables
UPDATE: I have used the Schur complement suggested from the follwing remark on another forum : So, I did the follwing modif...

presque 2 ans il y a | 0

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Filling symbolic arrays while setting zeros when filling these arrays since useless variables
Hello, below a code snippet to fill the symbolic matrixes FISH_BIG_GCsp and FISH_BIG_XC. Unfortunately, I am not filling entir...

presque 2 ans il y a | 1 réponse | 0

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MATLAB : find a way with GPU NVIDIA to inverse quickly a large matrix of symbolic variables
I have to solve the equality between 2 matrixes 12x12 containing a lot of symbolic variables and with which I perform inversion ...

presque 2 ans il y a | 3 réponses | 0

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system of 4 symbolic equations, one unknown and can't get a numerical value or symbolic expression for this unknown
I have a system of 4 symbolic equations, actually these come from the equality between 2 matrixes 2x2. I have only one unknown w...

presque 2 ans il y a | 1 réponse | 0

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MATLAB error on solving a system of equations : Error using sym.getEqnsVars>checkVariables (line 92)
I try to solve a system of equations with 3 unknowns called "` FISH_O_SYM(1,1),FISH_O_SYM(2,2),FISH_O_SYM(1,2) `" (the element...

presque 2 ans il y a | 1 réponse | 0

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How to find solutions for a matrix equality, i.e a system of equations ?
I would like to make work a small script. This Matlab code is expected to solve a matricial equation, but by equality of 2 final...

presque 2 ans il y a | 1 réponse | 0

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Problem when solving symbolically an equality between 2 matrices : issue when forcing symmetric matrices
I try to solve an equality between 2 matrices 3x3. There are, among all the parameters, 10 unknowns to find. 1) Here is the s...

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Error when trying to solve a "Matricial" equation : problem of indices
@Walter Roberson , Thanks for your quick answer. I tried like you suggested : eqn = FISH_GCsp_XC_SYM == FISH_GCsp_XC_SYM2; % ...

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Error when trying to solve a "Matricial" equation : problem of indices
Hello, I try to solve a system of equations (actually, this is like a "Matricial equations since I would like that each elemen...

presque 2 ans il y a | 2 réponses | 0

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Squeeze : Unable to perform assignment because the size of the left side is 1-by-7-by-7 and the size of the right side is 6-by-6
@Walter Roberson Hello, the previous error into qndiag has been fixed : Unable to perform assignment because the size of th...

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Squeeze : Unable to perform assignment because the size of the left side is 1-by-7-by-7 and the size of the right side is 6-by-6
@Walter Roberson I tried your solution by using [p, d] = eig(C_mean) or even : [p, d] = eigs(C_mean,7) But I still get...

environ 2 ans il y a | 0

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Squeeze : Unable to perform assignment because the size of the left side is 1-by-7-by-7 and the size of the right side is 6-by-6
Hello, I am trying to use qndiag (from https://github.com/pierreablin/qndiag.git ) from the following function : function [D, ...

environ 2 ans il y a | 3 réponses | 0

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Find the common eigenvectors and eigenvalues between 2 matrices
Hi Bruno ! Finally, I have just found a unique common eigenvector coming from : null(A*B-B*A) and which is equal to : ans = ...

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Compute approximative common eigenvectors basis between two matrices as a function of tolerance
By approximative, I mean that the eigenvectors of first matrix (passing matrix) looks like to the eigenvectors of second matr...

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Compute approximative common eigenvectors basis between two matrices as a function of tolerance
SUMMARIZE : Given 2 matrices A and B that don't commute, I am looking for finding or rather building an approximative common ei...

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Way to find common eigen vectors for a pair of matrices with known eigen values
Hello, I am looking for finding or rather building common eigenvectors matrix X between 2 matrices A and B such as : AX=aX ...

environ 2 ans il y a | 1 réponse | 0

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Find the common eigenvectors and eigenvalues between 2 matrices
Hello, I am looking for finding or rather building common eigenvectors matrix X between 2 matrices A and B such as : AX=a...

environ 2 ans il y a | 3 réponses | 1

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Matlab's GlobalSearch function : error message at execution
@Walter Roberson thanks, I provide all the code below. D1 and D2 are 7x7 diagonal matrices, F1, F1 and P1, P2 are 7x7 matrices....

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Matlab's GlobalSearch function : error message at execution
I have a system of matricial equations where I want to find 2 matrices of 7x7 (so I am working with (1x98) vectors). I have a...

environ 2 ans il y a | 2 réponses | 0

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Matlab - Solving a system of 2 matricial equations : building each element of matrix solution
With Matlab, I have a matrix solution to find from 2 matricial equations (size matrix is 7x7). Here the 2 equations to solve w...

environ 2 ans il y a | 1 réponse | 0

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Using fsolve in a loop with 2 unknown scalars to solve for each iteration
Hello, I would like to solve the couple (a,b) variables in a loop : this way, I would store each solution (a,b) in a vector vec...

environ 2 ans il y a | 1 réponse | 0

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