Beliebte Diskussionen

Andrew Janke
Andrew Janke
Letzte Aktivitätam 12 Jan. 2026 um 12:48

Let's say MathWorks decides to create a MATLAB X release, which takes a big one-time breaking change that abandons back-compatibility and creates a more modern MATLAB language, ditching the unfortunate stuff that's around for historical reasons. What would you like to see in it?
I'm thinking stuff like syntax and semantics tweaks, changes to function behavior and interfaces in the standard library and Toolboxes, and so on.
(The "X" is for major version 10, like in "OS X". Matlab is still on version 9.x even though we use "R20xxa" release names now.)
What should you post where?
Wishlist threads (#1 #2 #3 #4 #5): bugs and feature requests for Matlab Answers
Frustation threads (#1 #2): frustrations about usage and capabilities of Matlab itself
Missing feature threads (#1 #2): features that you whish Matlab would have had
Next Gen threads (#1): features that would break compatibility with previous versions, but would be nice to have
@anyone posting a new thread when the last one gets too large (about 50 answers seems a reasonable limit per thread), please update this list in all last threads. (if you don't have editing privileges, just post a comment asking someone to do the edit)
Paul
Paul
Letzte Aktivitätam 12 Jan. 2026 um 15:31

Inspired in part by Christmas Trees, I'm curious about people's experience using AI to generate Matlab code.
1. Do you use AI to generate production code or just for experimentation/fun code?
2. Do you use the AI for a complete solution? Or is it more that the AI gets you most of the way there and you have to apply the finishing touches manually?
3. What level of quality would you consider the generated code? Does it follow "standard" Matlab coding practices? Is it well commented? Factored into modular functions? Argument checking? Memory efficient? Fast execution? Etc.?
4. Does the AI ever come up with a good or clever solution of which you wouldn't have thought or maybe of which you weren't even aware?
5. Is it easy/hard to express your requirements in a manner that the AI tool effectively translates into something useful?
6. Any other thoughts you'd care to share?
Frequently, I find myself doing things like the following,
xyz=rand(100,3);
XYZ=num2cell(xyz,1);
scatter3(XYZ{:,1:3})
But num2cell is time-consuming, not to mention that requiring it means extra lines of code. Is there any reason not to enable this syntax,
scatter3(xyz{:,1:3})
so that I one doesn't have to go through num2cell? Here, I adopt the rule that only dimensions that are not ':' will be comma-expanded.
You may have come across code that looks like that in some languages:
stubFor(get(urlPathEqualTo("/quotes"))
.withHeader("Accept", equalTo("application/json"))
.withQueryParam("s", equalTo(monitoredStock))
.willReturn(aResponse())
.withStatus(200)
.withHeader("Content-Type", "application/json")
.withBody("{\\"symbol\\": \\"XYZ\\", \\"bid\\": 20.2, " + "\\"ask\\": 20.6}")))
That’s Java. Even if you can’t fully decipher it, you can get a rough idea of what it is supposed to do, build a rather complex API query.
Or you may be familiar with the following similar and frequent syntax in Python:
import seaborn as sns
sns.load_dataset('tips').sample(10, random_state=42).groupby('day').mean()
Here’s is how it works: multiple method calls are linked together in a single statement, spanning over one or several lines, usually because each method returns the same object or another object that supports further calls.
That technique is called method chaining and is popular in Object-Oriented Programming.
A few years ago, I looked for a way to write code like that in MATLAB too. And the answer is that it can be done in MATLAB as well, whevener you write your own class!
Implementing a method that can be chained is simply a matter of writing a method that returns the object itself.
In this article, I would like to show how to do it and what we can gain from such a syntax.
Example
A few years ago, I first sought how to implement that technique for a simulation launcher that had lots of parameters (far too many):
lauchSimulation(2014:2020, true, 'template', 'TmplProd', 'Priority', '+1', 'Memory', '+6000')
As you can see, that function takes 2 required inputs, and 3 named parameters (whose names aren’t even consistent, with ‘Priority’ and ‘Memory’ starting with an uppercase letter when ‘template’ doesn’t).
(The original function had many more parameters that I omit for the sake of brevity. You may also know of such functions in your own code that take a dozen parameters which you can remember the exact order.)
I thought it would be nice to replace that with:
SimulationLauncher() ...
.onYears(2014:2020) ...
.onDistributedCluster() ... % = equivalent of the previous "true"
.withTemplate('TmplProd') ...
.withPriority('+1') ...
.withReservedMemory('+6000') ...
.launch();
The first 6 lines create an object of class SimulationLauncher, calls several methods on that object to set the parameters, and lastly the method launch() is called, when all desired parameters have been set.
To make it cleared, the syntax previously shown could also be rewritten as:
launcher = SimulationLauncher();
launcher = launcher.onYears(2014:2020);
launcher = launcher.onDistributedCluster();
launcher = launcher.withTemplate('TmplProd');
launcher = launcher.withPriority('+1');
launcher = launcher.withReservedMemory('+6000');
launcher.launch();
Before we dive into how to implement that code, let’s examine the advantages and drawbacks of that syntax.

Benefits and drawbacks

Because I have extended the chained methods over several lines, it makes it easier to comment out or uncomment any one desired option, should the need arise. Furthermore, we need not bother any more with the order in which we set the parameters, whereas the usual syntax required that we memorize or check the documentation carefully for the order of the inputs.
More generally, chaining methods has the following benefits and a few drawbacks:
Benefits:
  • Conciseness: Code becomes shorter and easier to write, by reducing visual noise compared to repeating the object name.
  • Readability: Chained methods create a fluent, human-readable structure that makes intent clear.
  • Reduced Temporary Variables: There's no need to create intermediary variables, as the methods directly operate on the object.
Drawbacks:
  • Debugging Difficulty: If one method in a chain fails, it can be harder to isolate the issue. It effectively prevents setting breakpoints, inspecting intermediate values, and identifying which method failed.
  • Readability Issues: Overly long and dense method chains can become hard to follow, reducing clarity.
  • Side Effects: Methods that modify objects in place can lead to unintended side effects when used in long chains.

Implementation

In the SimulationLauncher class, the method lauch performs the main operation, while the other methods just serve as parameter setters. They take the object as input and return the object itself, after modifying it, so that other methods can be chained.
classdef SimulationLauncher
properties (GetAccess = private, SetAccess = private)
years_
isDistributed_ = false;
template_ = 'TestTemplate';
priority_ = '+2';
memory_ = '+5000';
end
methods
function varargout = launch(obj)
% perform whatever needs to be launched
% using the values of the properties stored in the object:
% obj.years_
% obj.template_
% etc.
end
function obj = onYears(obj, years)
assert(isnumeric(years))
obj.years_ = years;
end
function obj = onDistributedCluster(obj)
obj.isDistributed_ = true;
end
function obj = withTemplate(obj, template)
obj.template_ = template;
end
function obj = withPriority(obj, priority)
obj.priority_ = priority;
end
function obj = withMemory( obj, memory)
obj.memory_ = memory;
end
end
end
As you can see, each method can be in charge of verifying the correctness of its input, independantly. And what they do is just store the value of parameter inside the object. The class can define default values in the properties block.
You can configure different launchers from the same initial object, such as:
launcher = SimulationLauncher();
launcher = launcher.onYears(2014:2020);
launcher1 = launcher ...
.onDistributedCluster() ...
.withReservedMemory('+6000');
launcher2 = launcher ...
.withTemplate('TmplProd') ...
.withPriority('+1') ...
.withReservedMemory('+7000');
If you call the same method several times, only the last recorded value of the parameter will be taken into acount:
launcher = SimulationLauncher();
launcher = launcher ...
.withReservedMemory('+6000') ...
.onDistributedCluster() ...
.onYears(2014:2020) ...
.withReservedMemory('+7000') ...
.withReservedMemory('+8000');
% The value of "memory" will be '+8000'.
If the logic is still not clear to you, I advise you play a bit with the debugger to better understand what’s going on!

Conclusion

I love how the method chaining technique hides the minute detail that we don’t want to bother with when trying to understand what a piece of code does.
I hope this simple example has shown you how to apply it to write and organise your code in a more readable and convenient way.
Let me know if you have other questions, comments or suggestions. I may post other examples of that technique for other useful uses that I encountered in my experience.
Duncan Carlsmith
Duncan Carlsmith
Letzte Aktivitätam 7 Jan. 2026 um 5:36

I struggle with animations. I often want a simple scrollable animation and wind up having to export to some external viewer in some supported format. The new Live Script automation of animations fails and sabotages other methods and it is not well documented so even AIs are clueless how to resolve issues. Often an animation works natively but not with MATLAB Online. Animation of results seems to me rather basic and should be easier!
No, staying home (or where I'm now)
25%
Yes, 1 night
0%
Yes, 2 nights
12.5%
Yes, 3 nights
12.5%
Yes, 4-7 nights
25%
Yes, 8 nights or more
25%
8 Stimmen
Mirhan
Mirhan
Letzte Aktivitätam 12 Jan. 2026 um 12:24

Dear MATLAB Community,
I am working on a genetic algorithm (GA)–based optimization problem and would appreciate your insights.
In my model, the GA optimizes the x and y coordinates of a set of knots. These knots are then connected using NURBS to compute cross-sectional information. The number of decision variables is therefore 2N, where N is the number of knots.
The key GA parameters in my study are:
  • Number of knots (N)
  • Population size, defined as PopulationSize = PopulationMultiplier×N
  • EliteCount
  • CrossoverFraction
For example, when N=10 and the population multiplier is 200, the population size is 2000, which I believe is reasonable for a 20-variable problem.
My main objective is to understand how to select appropriate values for EliteCount, PopulationSize, and CrossoverFraction as the number of knots changes. However, when I analyze and plot the results, I do not observe a clear trend.
Intuitively, I expect that increasing the population size should allow the GA to better explore the search space and approach the global optimum more reliably. However, in some cases, increasing the population size results in very irregular or “weird” shapes in the optimized geometry.
I tested the following combinations:
%%% OPTIMIZATION DESIGN SPACE
NumberOfKnotsArray =[6 8 10];
%%% GA PARAMETERS
PopMultipArray = [200 400 800];
EliteCountArray = [0 5 10];
CrossoverFractionArray = [0 0.4 0.8];
As an example, one configuration is:
  • N=6
  • PopulationMultiplier = 200
  • EliteCount = 0
  • CrossoverFraction = 0
Based on my observations so far:
  • For small numbers of knots (e.g., N=4,5,6), changing GA parameters does not significantly affect the results; the algorithm seems robust enough in this regime.
  • As N increases, the behavior becomes less predictable, and no clear trend emerges with respect to GA parameter changes.
In my plots, the pink region represents the design space. The first and last knots are allowed to lie outside this space.
I would appreciate feedback on the following questions:
  1. Why might increasing the population size lead to unexpected or irregular solutions?
  2. Is it possible to identify a reasonably “global” GA parameter combination that works well across a wide range of knot numbers (at least up to some limit)?
  3. Is the assumption that a higher population size generally leads to better convergence to the global optimum or more reproducible results incorrect?
  4. Are there other important effects or interactions among these parameters that I should be considering?
Any comments, suggestions, or references would be greatly appreciated.
Thank you for your time and help.
Here is the expected result
Here are the GA results for different parameter combinations:

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