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# SA-W

Last seen: 15 jours il y a Actif depuis 2021

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matlab uitable: split columns into several rows
I construct an uitable from a struct like: % params is a struct T = struct2table(params); fields = fieldnames(params)'; fig ...

21 jours il y a | 1 réponse | 0

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graphical visualization of input parameters collected in a struct/array
My simulation depends on a whole bunch of input parameters that control various features of the simulation. I decided to group...

24 jours il y a | 2 réponses | 0

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Question

vectorize expression containing if statement
A = [-5 3 2;2 3 4; 3 5 6; -2 8 9]; %compute product of columns in a vectorized fashion A(:,1).*A(:,2).*A(:,3); %calculate the...

3 mois il y a | 1 réponse | 0

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tall array introduces significant overhead if I call gather() at every iteration in a loop
I want to figure out the spread of the invariants of a symmetric 3x3 matrix using the code below %input nPts = 2; ub = 2.0; ...

3 mois il y a | 1 réponse | 0

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out-of-memory because of large array: tall array as a workaround?
Given a symmetric, positive definite 3x3 matrix (6 independent components), I want to figure out the spread of the first and sec...

3 mois il y a | 1 réponse | 0

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Question

how can I increase the performance of this loop?
nPts = 15; a = linspace(0.1, 2.0, nPts); b = linspace(0.1, 2.0, nPts); c = linspace(0.1, 2.0, nPts); d = linspace(-0.3, 2....

3 mois il y a | 1 réponse | 0

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scatteredInterpolant: what is linear interpolation in 2d?
%coords supportPts = [3 3; 3.3 3; 3 3.25; 3.3 3.25; 3.6 3; 3.6 3.25; 3 3.5; 3.3 3.5; 3.6 3.5]; %values Fval = [0 0.1121 0.064...

3 mois il y a | 1 réponse | 0

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can I pass these nonlinear constraints to lsqnonlin?
residual =[residual; smallnumber*[diff(G,2);diff(H,2)]] This is an equivalent way to implement my suggestion I just realize th...

3 mois il y a | 0

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c++ engine API: minimal example gives segmentation fault, see stacktrace
I built an c++ API engine using a minimal example as shown here https://de.mathworks.com/help/matlab/matlab_external/test-your-...

3 mois il y a | 1 réponse | 0

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Question

bilinear extrapolation based on interp2
[X,Y] = meshgrid(0:10); Z = X.^2 + Y.^2; [Xq,Yq] = meshgrid(0:0.25,10); V = interp2(X,Y,Z,Xq,Vq,'linear'); I want to use int...

4 mois il y a | 2 réponses | 1

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can I pass these nonlinear constraints to lsqnonlin?
Let denote a function of two variables and the parameters of the optimization problem which I want to solve with lsqnonli...

4 mois il y a | 3 réponses | 0

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symbolic differentiation to find analytical expressions that are time-consuming to calculate manually?
Given a function of two variables f(x,y) = I want to find the analytial expression of the determinant of the Hessian of . ar...

4 mois il y a | 1 réponse | 0

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lsqnonlin optimization: large condition number of Jacobian matrix at all iterations, but full rank
I use lsqnonlin to solve a non-linear data-fitting problem (fitting parameters of a partial differential equation). The minimiza...

4 mois il y a | 2 réponses | 1

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Question

source code of multistart in global optimization toolbox
I am currently using multistart to perform optimization with multiple start vectors. ms = Multistart(...) ... = run(ms,...) ...

4 mois il y a | 1 réponse | 0

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Question

import bubblechart in latex document and typeset text (x-labels,...) by latex -- possible?
I created two bubblecharts next to each other in a tiledlayout(1,2) and want to include it in my tex document. Both matlab2tikz...

7 mois il y a | 1 réponse | 0

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Question

gradient of bubble colors in a bubble chart
I want to create a bubblechart with three different bubble colors. One group of bubbles is red, the second group is blue, and ...

7 mois il y a | 1 réponse | 0

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natural cubic spline interpolation of y-values: how to get derivative of the spline wrt the y-values?
Given a data set with support points x_1,...,x_n and corresponding y-values y_1,...,y_n. My objective is to create a cubic spli...

7 mois il y a | 3 réponses | 0

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optimization: have function return NaN but not at initial point
I use fmincon interior-point algoritm to solve my optimization problem. Based on Matlab's recommendation, I let my function re...

7 mois il y a | 1 réponse | 1

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Question

is the objective function stochastic (-> use something like patternsearch) or deterministic?
My objective function is given by f(x) = ||d^sim(x) - d^exp||^2 d^exp is a constant vector of measurements, to which I add ra...

7 mois il y a | 1 réponse | 0

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what is a reasonable step tolerance for optimization algorithms if parameters are in the range [0,1]?
My parameters are bounded from below by zero and from above by roughly one. I recently worked with a quite small step tolerence...

7 mois il y a | 1 réponse | 0

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fmincon: any way to enforce linear inequality constraints at intermediate iterations?
I am solving an optimization problem with the interior-point algorithm of fmincon. My parameters have both lower and upper boun...

7 mois il y a | 3 réponses | 1

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alternatives to gradient-based optimization algorithms like lsqnonlin that handle at least O(10) parameters?
I am fitting parameters of a PDE to experimental data utilizing the function lsqnonlin from the optimization toolbox. I obser...

7 mois il y a | 2 réponses | 0

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Question

trust-region reflective algorithm in lsqnonlin and fmincon: same behavior for "unconstrained" optimization"?
Say I provide constraints to lsqnonlin and fmincon. For both, I will choose trust-region-reflective algorithm Do both fmincon a...

8 mois il y a | 1 réponse | 1

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Question

multistart optimization: local run index of solutions found by [...,solutions] = run(__)?
I am running my optimization problem with several start vectors utilizing the function [x,fval,exitflag,output,solutions] = run...

8 mois il y a | 1 réponse | 0

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Question

importdata produces strange output when reading a textfile with blank cells and text
I want to import the attached file which is the result of matlabs function run. As you can see, there are a couple of blank cell...

8 mois il y a | 2 réponses | 0

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lsqnonlin with multiple start vectors: continue with next start vector if the function computing the objective function sets a "flag"
I want to execute lsqnonlin with multiple start vectors by iterating over a for-loop. If the function called by lsqnonlin (here,...

8 mois il y a | 2 réponses | 0

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add (white) Gaussian noise to displacement signal, noise level = ( |x-x*| / |x*| ): can I use utilize awgn()?
I want to add artificial (white) Gaussian noise to my numerically generated signal. In the title of my question, x %is the dis...

9 mois il y a | 1 réponse | 0

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Check Gradient (Jacobian) of objective function -- what is the meaning of absolute difference (1e-6) if component of gradient is less than 1 ?
I use lsqnonlin to solve my data-fitting problem and provide the Jacobian, which I verify using CheckGradients option. As state...

9 mois il y a | 1 réponse | 0

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Question

is randn() appropriate to emulate noise coming from digital image correlation?
I want to emulate experimental data coming from an digital image correlation (DIC) system. Currently, I generate the displacemen...

9 mois il y a | 1 réponse | 0

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Question

element-wise operator to scale rows of matrix with entries of a vector
Given a matrix and a vector A = [2 3 4 5;5 4 3 2;1 2 3 4;4 3 2 1]; d = [1 2 3 4]; I want to scale the rows of A with the corr...

9 mois il y a | 1 réponse | 0

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