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Adam and Heather will be discussing new features in R2023b and answering your questions in a few hours - visit the link below to check out the preview and sign up for notification.
https://www.youtube.com/watch?v=mImQs4PfioM
Adam Danz just launched a new blog about MATLAB Graphics and App Building.
https://blogs.mathworks.com/graphics-and-apps/2023/10/10/welcome/
As you know, He has been a prolific contributor to MATLAB Answers and one of his answers recently won the Editor's Choice Award.
If there are any topics or questions you are interested in, please share with Adam, and I am sure he will get those into his blog.
Adam Danz
Adam Danz
Last activity il 13 Ott 2023

Approximating π with durations

Over the weekend I came across a pi approximation using durations of years and weeks (image below, Wolfram, eq. 89), accurate to 6 digits using the average Gregorian year (365.2425 days).
Here it is in MATLAB. I divided by 1 week at the end rather than multiplying by its reciprocal because you can’t divide a numeric by a duration in MATLAB (1/week).
weeks = @(n)n*days(7);
piApprox = ((years(13)-weeks(6))/years(13) + weeks(3)) / weeks(1)
% piApprox = 3.141593493469302
Here’s a breakdown
  • The first argument becomes 12.885 yrs / 13 yrs or 0.99115
  • Add three weeks: 0.99115 + 3 weeks = 21.991 days
  • The reduced fraction becomes 21.991 days / 7 days
Now it looks a lot closer to the more familiar approximation for pi 22/7 but with greater precision!
Adam Danz
Adam Danz
Last activity il 6 Mar 2024

To hold or not to hold

I'm curious how the community uses the hold command when creating charts and graphics in MATLAB. In short, hold on sets up the axes to add new objects to the axes while hold off sets up the axes to reset when new objects are added.
When you use hold on do you always follow up with hold off? What's your reasoning on this decision?
Can't wait to discuss this here! I'd love to hear from newbies and experts alike!
The way we've solved ODEs in MATLAB has been relatively unchanged at the user-level for decades. Indeed, I consider ode45 to be as iconic as backslash! There have been a few new solvers in recent years -- ode78 and ode89 for example -- and various things have gotten much faster but if you learned how to solve ODEs in MATLAB in 1997 then your knowledge is still applicable today.
In R2023b, there's a completely new framework for solving ODEs and I love it! You might argue that I'm contractually obliged to love it since I'm a MathWorker but I can assure you this is the real thing!
I wrote it up in a tutorial style on The MATLAB Blog https://blogs.mathworks.com/matlab/2023/10/03/the-new-solution-framework-for-ordinary-differential-equations-odes-in-matlab-r2023b/
The new interface makes a lot of things a much easier to do. Its also setting us up for a future where we'll be able to do some very cool algorithmic stuff behind the scenes.
Let me know what you think of the new functionality and what you think MathWorks should be doing next in the area of ODEs.
4 months ago, the new API was published to access content on the MATLAB Central community. I shared my MATLAB code to access the API at that time, but the team just released the official SDK.
MATLAB toolbox on File Exchange: https://www.mathworks.com/matlabcentral/fileexchange/135567-matlab-central-interface-for-matlab
Node.js package on NPM: https://www.npmjs.com/package/matlabcentral
Public API Doc: https://api.mathworks.com/
Houman and Rameez will talk about how you can model wireless networks (5G, WLAN, Bluetooth, 802.11ax WLAN mesh, etc.) in MATLAB in the upcoming livestream. They will start with the basics such as nodes, links, topology and metrics. Then they will introduce a new free add-on library that lets you model such networks, and show you how to use it.
Bookmark this link:
https://www.youtube.com/watch?v=2EFpUd5aTFw
Congratulations, @Adam Danz for winning the Editor's Pick badge awarded for MATLAB Answers, in recognition of your awesome solution in overlapping images in grid layout.
Thank you for going to great lengths to help a user in this thread by suggesting alternative approach to representing stack of playing cards in MATLAB, highlighting very interesting features like hggroup.
This badge recognizes awesome answers people contribute and yours was picked for providing a very detailed and helpful answer.
Thank you so much for setting a high standard for MATLAB Answers and for your ongoing contribution to the community.
MATLAB Central Team
Congratuations, @Voss, for htting this important miletone!
You had a meteoric rise to in our community since you started answering questions in June 2020.
You provided 3218 answers and 926 votes. You are ranked #23 in the community. Thank you for your contribution to the community and please keep up the good track record!
MATLAB Central Team
MATLAB Onramp is a free online tutorial and it has been very popular with new MATLAB users to learn how to use it, and MathWorks have been adding more and more modules. The lastest one just dropped https://matlabacademy.mathworks.com/details/power-systems-simulation-onramp/orps
It shows you the basics of power system simulation by modeling a simple microgrid. You will learn how to simulate and measure three-phase circuits, and how to evaluate algorithms like droop control and maximum power point tracking.
Here's a screenshot from 22 years ago. Thanks for building one of the best engineering and science communities together.
Image Analyst
Image Analyst
Last activity il 22 Lug 2024

My preferred vacation is to visit

cities
15%
beaches, islands, or cruises
22%
rivers, lakes, or mountains
33%
National Parks or historical sites
14%
wherever my family lives
12%
somewhere else
5%
13709 voti
Hello, an intern working at MathWorks is finishing up his program soon and he would like to interview some MATLAB users. He is looking for people who can give their perspective on the question:
"What makes MATLAB and Simulink special in comparison to other languages?"
Ultimately he plans to condense the answers into 15-second videos or sound bites.
If people are willing to participate but want more time to talk about their experience with MATLAB, he doesn't have time left for in-depth interviews but he can find someone else to take over the project.
Please send me an email via my profle if you are interested.
https://www.mathworks.com/matlabcentral/profile/authors/951521
Yes, in my company that I own
35%
Yes, for someone else (or Univ.)
21%
Only for free, for charities
13%
Only in my charitable foundation
5%
No, I'd just play, travel, & relax
25%
15668 voti
1
33%
2
34%
3
18%
4
5%
5
3%
6+
6%
1643 voti
Image Analyst
Image Analyst
Last activity il 19 Ago 2023

The glass is ...

half full.
12%
half empty.
4%
both.
12%
twice as big as it needs to be.
15%
1/2 full of beer, 1/2 full of air.
17%
What glass???
39%
6618 voti
The MATLAB Answers community is an invaluable resource for all MATLAB users, providing selfless assistance and support. However, with the emergence of AI-based chatbots, like chatGPT, there may be concerns about the future relevance and utility of the MATLAB Answer community. What are your thoughts?
figure out what my old code does
18%
write code comments for future me
11%
address a code analyzer warning
3%
reflect on the skills I've gained
8%
get food on my mouse and keyboard
38%
All of the above
22%
16434 voti
Getting Started with Simulink | Tips and Tricks to Get the Most Out of Simulink
Watch live as Tianyi Zhu and Ashwin Dhawad walk through how you can get started with Simulink by modeling, simulating, and tuning a PID controller for a DC Motor. This session isn’t just for beginners; they will show you the latest and greatest tips and tricks to help you get the most out of Simulink.
Date & Time: May 25, 2023 at 11:00 am EDT (see time in your time zone)
https://www.youtube.com/watch?v=Iu4M3dD0kPQ
MATLAB Central has been great community-based MATLAB resources, but you can now access its content programmatically via the public API, and I created a MATLAB function to take advantage of that. You can learn more here https://api.mathworks.com/community
Example:
data = searchMATLABCentral("plotting",scope="matlab-answers",sort_order="created desc",created_after=datetime("2023-01-01"));
T = struct2table(data.items);
T(:,["created_date","title","is_answered"])
Output
Function
function results = searchMATLABCentral(query,options)
% SEARCGMATLABCENTRAL retrieves content of the MATLAB Central for a given
% query and returns the result as a struct.
% The function uses MathWorks RESTful API to search for content.
% The API is rate limited via IP throttling. No authentication is required.
% See API documentation for more details https://api.mathworks.com/community
%
% Input Arguments:
%
% query (string) - Required. The search query string.
% scope (string) - Optional. Specify the artifact. If not specified,
% the scope defaults to 'matlab-answers'.
% Other options include 'file-exchange','blogs','cody',
% 'community-highlights', and 'community-contests'.
% tags (string) - Optional. Specify a comma-separated list of tags.
% created_before (datetime) - Optional. Specify the last date in the results
% created_after (datetime) - Optional. Specify the first date in the results
% sort_order (string) - Optional. Speficy the order of the results.
% If not specified, it defaults to "relevance desc".
% Other options include 'created asc', 'created desc',
% 'updated asc','updated desc', 'relevance asc',
% and 'relevance desc'.
% page (integer) - Optional. Specify the page to retrieve.
% If the 'has_more' field in the result is positive,
% increment this argument to retrieve the next page.
% count (integer) - Optional. Specify the number of results as a value
% between 1 and 50; The default is 10.
%
% Output Arguments:
%
% results (struct) - Structure array containing the results of the search.
% validate input arguments
arguments
query string {mustBeNonzeroLengthText,mustBeTextScalar}
options.scope string {mustBeMember(options.scope,["matlab-answers", ...
"file-exchange","blogs","cody","community-highlights", ...
"community-contests"])} = "matlab-answers";
options.tags string {mustBeNonzeroLengthText,mustBeVector}
options.created_before (1,1) datetime
options.created_after (1,1) datetime
options.sort_order string {mustBeMember(options.sort_order,["created asc", ...
"created desc","updated asc","updated desc","relevance asc","relevance desc"])}
options.page double {mustBeInteger,mustBeGreaterThan(options.page,0)}
options.count double {mustBeInteger,mustBeInRange(options.count,1,50)}
end
% API URL and endpoint
url = "https://api.mathworks.com/community";
endpoint = "/v1/search";
% convert MATLAB datetime to the internet datetime format string
if isfield(options,"created_before")
options.created_before = string(options.created_before,"yyyy-MM-dd'T'HH:mm:ss'Z'");
end
if isfield(options,"created_after")
options.created_after = string(options.created_after,"yyyy-MM-dd'T'HH:mm:ss'Z'");
end
% convert optional inputs into a cell array of key-value pairs
keys = fieldnames(options);
vals = struct2cell(options);
params = [keys,vals].';
% call the API
try
results = webread(url+endpoint,"query",query,params{:});
catch ME
rethrow(ME)
end
end