# Alan Weiss

### MathWorks

I write documentation for MATLAB mathematical toolboxes, primarily optimization. I have also written documentation for PDE, statistics, symbolic math, and econometrics.

My pre-MathWorks job was with Bell Labs, primarily in mathematical models of data traffic, with a strong interest in parallel computation and in rare events (large deviations).

I do not provide private consulting. If you have a question, please ask on a public forum such as MATLAB Answers.

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**Content Feed**

Optimization FlowShop Problem- Error Received

You don't pass numJobs into your calculateMaxTardinessWithSequence function: function maxTardiness = calculateMaxTardinessWithS...

10 giorni fa | 0

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Why are the return results of the fcn2optimexpr function different between MATLAB2019b and MATLAB2023b?

I think that you need to turn off static analysis: [f,exitflag] = fcn2optimexpr(@mubiaofunction,x,Analysis="off") Alan Weiss ...

10 giorni fa | 0

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Global Optimisation and nested function problem

The reason objective_function can see those parameters is because you passed them into the Fitautocorrvins function, and that is...

24 giorni fa | 1

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Solve using genetic algorithm

I really don't understand what you are trying to do. You seem to be mixing up symbolic and numeric variables. If you want to use...

24 giorni fa | 1

Giving target function outputs to optimization algorithm

While I haven't tried this before, it sounds to me as if you could change your objective function to use a data set of known poi...

circa un mese fa | 0

Number of plots by gaplotpareto

If I understand your question, you are asking either How does the solver choose the number of points to plot? Or How does the ...

3 mesi fa | 1

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Optimization problem gets stuck before going into solver

It is apparent that solve is taking too long to calculate constraint derivatives using reverse-mode autodifferentiation. This mi...

3 mesi fa | 0

Optimizing the GRU training process using Bayesian shows errors

The error is coming from your code. Apparently, some points visited (that have, for example, NumOfUnits = 30, InitialLearnRate =...

3 mesi fa | 0

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Gaussian process regression - how to fit a basis function but not other parameters

I might misunderstand what you are trying to do, but perhaps you could use the OptimizeHyperparameters name-value argument to fi...

6 mesi fa | 0

When I use fmincon, the optimised result does not satisfy my non liner constraints

You would do better to use the default 'interior-point' algorithm, which arrives at a feasible solution. fun = @(x)4*x(1)+x(2);...

6 mesi fa | 0

How to use both pswplotbestf and pswplotranges for particleswarm?

The issue is that the pswplotranges output function was written incorrectly, and does not take into account that other plots mig...

6 mesi fa | 0

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Genetic Algorithm (ga) terminating after a few generations

Almost certainly this is because you use nonlinear constraints. When you use nonlinear constraints, there are very few major ite...

6 mesi fa | 0

HELP 3 variable optimization use fmincon

The short answer is you put all your variables into one variable, and call a solver on the one variable objective function. For ...

7 mesi fa | 0

How is genetic algorithm function's ga optimfunctions used? How do I use that? What is the difference between optimset and optimfunction? Why do I receive error in this code?

The correct function name is optimoptions: ga_opt = optimoptions('ga','Display', 'off', 'Generations', 25, 'PopulationSize',50,...

7 mesi fa | 1

How to obtain the optimised decision variable in the lower-layer when using genetic algorithm for a two-layer optimisation problem?

You can write these to an array, if you like. Something like this: function [DV_Up_Opt,Obj_Up_Opt,lowhistory] = myfun() lowhis...

7 mesi fa | 0

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fmincon non-linear optimisation: issues with sqp and interior-point

It sounds like you have done a good job in analyzing the solver behavior. There is one more thing that I have found that sometim...

8 mesi fa | 0

Solve linear equation optimization

You might find the examples in the linprog documentation useful. Alan Weiss MATLAB mathematical toolbox documentation

8 mesi fa | 0

pattern search does not perform function calculation between iterations.

I suggest that you turn on iterative display. I suspect that most of the values patternsearch samples evaluate to NaN or Inf or ...

9 mesi fa | 0

I want to fit my ode model to experimental data and derive parameters using lsqcurevfit and fmincon

There are some examples in the documentation of fitting ODE parameters to data: Fit ODE Parameters Using Optimization Variables...

9 mesi fa | 0

Can I adjust patternsearch meshsize using output function (during optimisation)?

Sorry to say, but a patternsearch output function does not allow you to change the mesh size. However, as I think you know, the ...

9 mesi fa | 0

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how does check gradient compare supplied gradients with finite difference gradients?

The CheckGradients option causes solvers to compare a finite-difference gradient estimate to the supplied gradient value, and if...

10 mesi fa | 0

Running genetic algorithm and Simulink in parallel

I am not at all sure that it is possible to run ga in parallel when the objective function is given by a Simulink model. For a ...

10 mesi fa | 1

optimising hybrid energy design using genetic algorithm

For an error of that type I think that you should learn to use the debugger. See Debug MATLAB Code Files and Set Breakpoints. A...

10 mesi fa | 0

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Fitness Scaling Options for Genetic Algorithm

The documentation says this: 'fitscalingrank' — The default fitness scaling function, 'fitscalingrank', scales the raw scores b...

10 mesi fa | 0

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Problems with lsqnonlin - initial parameters not changing

We don't see your ObjFunE code, so cannot be sure of what is going on. It seems that you are solving an ODE to create some outpu...

10 mesi fa | 0

Issue with large memory required for non-linear optimizer

You have 150^2 optimization variables. I do not see your parameterfun function, but if it is not a supported function for automa...

10 mesi fa | 1

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How to create a Triple Objective Genetic Algorithm establish constraints and plot 3D

I am sorry to say that I think that you need more help than we can give on this forum. If you want to have a productive interact...

10 mesi fa | 0

How to create a Triple Objective Genetic Algorithm establish constraints and plot 3D

OK, it seems that you have decided to use the solver-based approach, which is just fine. You set some nondefault options. I am ...

10 mesi fa | 0

How to prevent ga-Solver from accepting the first best solution?

It is possible that you unknowingly set some constraints that keep the solution you want from being considered. It is very hard ...

11 mesi fa | 0

Correct implementation of multi start option with pre-specified starters

If you read the description of MultiStart run, you see that calling run(ms,problem,k)) uses k - 1 random points in addition to t...

11 mesi fa | 0

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