Community Profile Alan Weiss

MathWorks

Last seen: Today Active since 2011

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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find the minimum objective for a given ode as boundary value problem
For examples of optimizing a function given as the solution to an ODE, see Fit ODE, Problem-Based and Fit an Ordinary Differenti...

1 dag ago | 0

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change number of pareto point with change number of initial population gamultiobj

2 dagen ago | 1

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FMINCON requires the following inputs to be of data type double: 'X0'.
Without testing anything, I see a problem in this line of code: fun = @(X0,StoreInitialization,ttransij1,texeij1,theta,D_Cloud,...

6 dagen ago | 1

GA is not satisfying nonlinear constraints
The answer is that you cannot ensure that nonlinear constraints are satisfied at every step. Instead, your code must accept poin...

11 dagen ago | 0

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What is penalty value in GA
The documentation describes the penalty value. As for the lower-left portion of the plot, these points are infeasible. Once ga ...

11 dagen ago | 0

how to use live editor optimize tool ?
Did you try the documentation examples? Solve a Constrained Nonlinear Problem, Solver-Based Get Started with Optimize Live Edi...

13 dagen ago | 0

how to use fsolve with multiple variables with unique names, not vectors
The Problem-Based Workflow for Solving Equations is designed to do exactly what you want. Alan Weiss MATLAB mathematical tool...

16 dagen ago | 1

A genetic algorithm code with constraints on individuals
I cannot understand much of what you say, but it sounds as if you are trying to give bounds on the solution. If I understand you...

26 dagen ago | 0

How do I use the max() function on an optimization expression when using the genetic algorithm?
If you check the Supported Operations for Optimization Variables and Expressions, you see that max is not supported. (Why? I bel...

26 dagen ago | 1

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Optimization using fmincon with respect to 2 variables
I think that you would find it much easier to use the problem-based approach rather than fmincon directly. The reason is that wi...

28 dagen ago | 0

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Problem-based optimization, Conversion to double from optim.problemdef.OptimizationExpression is not possible.
To use a general nonlinear function with an optimization variable, you must first convert the function to an optimization expres...

ongeveer een maand ago | 1

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I have problem with fmincon
Do not use symbolic variables with Optimization Toolbox functions, unless you convert them to function handles using matlabFunct...

ongeveer een maand ago | 0

Optimization method for solving mixed discrete-continuous programming problems
For linear objective and constraints, use intlinprog. For nonlinear objective or constraints, use ga or surogateopt from Global...

ongeveer een maand ago | 0

how to solve a cubic equation where the last term is an array
Try this instead of your code after %EVERYTHING UP TO HERE IS FINE: sol_x = zeros(size(V_total)); for i = 1:numel(V_total) ...

ongeveer een maand ago | 0

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optimization value not able to acheive
That is not what I get when I run your code: No solution found. fsolve stopped because the last step was ineffective. Howeve...

ongeveer een maand ago | 0

Using the output of a ready function as a constraint
I think that the easiest approach is problem-based. Create optimization variables: the vector A in your case Create the object...

ongeveer een maand ago | 0

Cancel objective function evaluation in Optimization
I think that you can write an output function for the ODE solver that will halt the solver if it takes too long or reaches too l...

ongeveer 2 maanden ago | 0

How to write the equation for minimizing one day power loss of a PV system as an objective function to be used in Genetic Algorithm.
I think that you need to rethink your objective function. It sounds like the input variables must be integers in a certain range...

ongeveer 2 maanden ago | 0

Define a optimization problem
Perhaps you left out constraints that the x, y, and z variables should be nonnegative. Put those constraints and the upper bound...

ongeveer 2 maanden ago | 0

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How to write the equation for minimizing one day power loss of a PV system as an objective function to be used in Genetic Algorithm.
Your function as written does not make use of the input x1 and x2 values. Instead, it declares these variables as indices for tw...

ongeveer 2 maanden ago | 0

Confusion over use of fmincon for an optimisation problem
There could be several reasons for your results, in addition to the hard-to-diagnose bugs and other programming errors. One is ...

ongeveer 2 maanden ago | 0

fsolve gives the same value for different parameters of the nonlinear equation
Your function funH returns the following iinternal values for your initial point x0 = 5 and the other parameters pmt = [1.027313...

ongeveer 2 maanden ago | 0

What does relative constraint tolerance of fmincon in detail ?
As far as the interpretation, a positive value means at least one constraint is violated. A zero (or negative for other solvers)...

ongeveer 2 maanden ago | 0

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Find gradient ascent for 3D surface
You might be interested in this example: Pattern Search Climbs Mount Washington Alan Weiss MATLAB mathematical toolbox documen...

ongeveer 2 maanden ago | 0

how to run different for loops in MATLAB
Usually, people write functions that accept arguments and return arguments, such as result(k,z,q) = Matlaboptimization(Pemax,Pb...

ongeveer 2 maanden ago | 0

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The running time complexity of Mixed-integer linear programming (MILP)?
It is well known that MILP is an NP-complete problem. See https://en.wikipedia.org/wiki/Integer_programming for an explanation. ...

ongeveer 2 maanden ago | 0

Matlab Optimisation toolbox (Score Constaint)
Instead of minimizing TARGETVALUE - ACTUALVALUE , instead minimize either abs(TARGETVALUE - ACTUALVALUE) or (TARGETVALUE - ACTUA...

ongeveer 2 maanden ago | 0

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Hi, I have been trying to carry out the mole balance of certain reactions on excel, but the equations have refused to converge, hence my switch to matlab.
You have a set of linear equations. You can represent your equations in terms of a matrix A and vector b in the usual framework ...

ongeveer 2 maanden ago | 1

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Energy storage optimisation problem - separate charge and discharge constraint
You are mixing up the problem-based and solver-based formulations. You need to choose one or the other. If you are using the sol...

ongeveer 2 maanden ago | 1

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