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This is a great presentation from 2 professors introducing how they use MATLAB in their physics courses. MATLAB Grader and Live Scripts are discussed in detail.

YouTube Video

Here is the abstract:

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Guest Presenters: Michele McColgan, Siena College and Duncan Carlsmith, UW Madison

The meeting will start with short presentations, and then we'll have time for questions and discussion in a colloquial setting. The presenters use MATLAB in their courses, and this meeting will provide a good opportunity to see the functionality that MATLAB affords. However, the presenters' approach to integrating computation is relevant generally; thus, this meeting should be of great interest, even if you are not a MATLAB user.

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Webinar from PICUP .

Prof. Duarte Antunes from Eindhoven University of Technology explains how he's been using MATLAB live scripts for teaching an online "Optimal Control and Dynamic Programming" course.

https://www.mathworks.com/company/newsletters/articles/using-matlab-live-scripts-to-teach-optimal-control-and-dynamic-programming-online.html

WiDS Datathon 2021 is going on right now. The focus of the Datathon this year is "on creating models to classify whether patients have been diagnosed with a certain type of diabetes." You can register and participate until March 1.

Also, take a look at this blog post on the MATLAB benchmark code for this datathon.

MATLAB Benchmark Code for WiDS Datathon 2021

There are also various online challenges by MathWorks that students may be interested. Here are the winners from last year's Simulink Student Challenge. There was also a MATLAB Online Live Editor Challenge a couple of years ago.

Hello , I wonder how to determine continous or discrete time modelling.For example if I want to run my model in MCU in this case discrete model is suitable?I am a bit confused

MATLAB Answers will now properly handle the use of the '*@*' character when you want to get someone's attention. This behavior is commonly referred to as 'mentioning' or 'tagging' someone and is a feature found in most communication apps.

Why we are doing this

To help with communication and potentially speed up conversations. Also, it turns out many of you have been typing the @ character in Answers already, even though the MATLAB Answers site didn't behave in the expected way.

How it works

Once you type the @ character a popup will appear listing the community members already in the Q/A thread, as you keep typing the list will expand to include members not in the thread. A mentioned user will receive a notification when the question/answer/comment is posted. Each mention in the Q/A thread will have a new visual style and link to the user profile for that community member.

If you don't want to get 'mentioned' you can turn off the setting in your communication preferences located on your profile page .

We hope you will find this feature helpful and as always please reply with any feedback you may have.

We have created a new community for users of ThingSpeak. This new community is for students, researchers, and engineers looking to use MATLAB, Simulink, and ThingSpeak for Internet of Things applications. You can find the latest ThingSpeak news, tutorials to jump-start your next IoT project, and a forum to engage in a discussion on your latest cloud-based project. You can see answers to problems other users have solved and share how you solved a problem.

Christopher Stapels will be moderating the new ThingSpeak community .

We encourage you to visit the new community and share best practices, examples, and ask questions.

Happy New Year, everyone! We hope you enjoyed the Cody contest in 2020, learned new MATLAB skills, and made a friend or two. While the 2020 contest has concluded, the fun and learning never end.

Please take the 1-minute survey to talk about your experience (only 2 required questions). Our goal is to make future contests better and more appealing to you, so your feedback is critical to us.

Thank you in advance and hope to see you again in the 2021 contest.

Here's an example of virtualizing a lab course.

https://www.mathworks.com/company/newsletters/articles/virtualizing-electrical-engineering-teaching-labs.html

Ameer Hamza had a great 2020 and has been awarded the coveted MOST ACCEPTED answers badge for all his contributions in MATLAB Answers this past year. Ameer joins Walter Roberson and Image Analyst in receiving this award going all the way back to 2012!

There are 10 community members who have achieved the Top Downloads badge for their popular File Exchange submissions in 2020. Do you recognize any of these names? There's a good chance you've used one or more of their toolboxes or scripts in your work if you're a frequent visitor to File Exchange, if you're not you might want to check out what they've posted, it may save you a lot of time writing your own code.

--------------------- Top Downloads Badge Winners -----------------

• PIRC
• Scott Lowe
• Yair Altman
• Dr. Siva Malla
• Chad Greene
• Seyedali Mirjalili
• Giampiero Campa
• Rodney Tan
• John D'Errico
• Steve Miller

Congratulations to all these winners and a giant THANK YOU for all they've done this past year to help everyone in the MATLAB Central community!

I am currently working on simulink online but I cannot maximize the screen

Just making sure people are aware of our new Onramp courses. These are great self-learning resources for students.

Released a few months ago:

• Image Processing Onramp
• Control Design Onramp with Simulink

Released this month:

• Signal Processing Onramp

How do you teach subjects like Programming and Numerical Computing hands-on in these challenging times?

Prof Chiranjoy Chattopadhyay at the Dept of Computer Science and Engineering at IIT Jodhpur shares his innovative approach to teaching at a distance in this new Technical Article on Teaching Parallel Computing Online with MATLAB.

The course utilized MATLAB Online , MATLAB Onramp and MATLAB Grader to train students in the basics of technical computing, in addition to using a Hands-on Online GPU workshop organised with the MathWorks Education Team. As a result of this approach to distance teaching, the students have reported good levels of understanding in the main learning outcomes of this course, as indicated in the survey results (below):

Please consider trying out the links above to check if your course might benefit from a similar approach, and feel free to message us if you are interested in learning more.

I just highlighted an app on File Exchange for emulating an experiment. Great idea for doing lab classes with software. What I like about this app is that it incorporates statistical variance and measurement noise that comes from physical experiments.

Read more about it here:

https://blogs.mathworks.com/pick/2020/11/20/emulating-a-physical-experiment-of-measuring-mms/

I would like to plot 2 discrete vectors on one graph created as follows: u=1; X={u,2*u,3*u,4*u,5*u,6*u,7*u,8*u,9*u}; Y={u,3*u,5*u,-u,-6*u,u-u,u^2,u^3,u^4}; stem(X,Y) unfortunately system returns error how to do it properly?

1. Use the new exportapp function to capture an image of your app|uifigure
2. MATLAB's getframe now supports apps & uifigures
3. Review: How to get the handle to an app figure

Use the new exportapp function to capture an image of your app|uifigure

Imagine these scenarios:

• Your app contains several adjustable parameters that update an embedded plot and you'd like to remember the values of each app component so that you can recreate the plot with the same dataset
• You're constructing a manual for your app and would like to include images of your app
• You're app contains a process that automatically updates regularly and you'd like to store periodic snapshots of your app.

As of MATLABs R2020b release , we no longer must rely on 3rd party software to record an image of an app or uifigure.

exportapp(fig,filename) saves an image (JPEG | PNG | TIFF | PDF) of a uifigure ( fig) with the specified file name or full file path ( filename). MATLAB's documentation includes an example of how to add an [Export] button to an app that allows the user to select a path, filename, and extension for their exported image.

Here's another example that merely saves the image as a PDF to the app's main folder.

1. Add a button to the app and assign a ButtonPushed callback function to the button. This one also assigns an icon to the button in the form of an svg file.

2. Define the callback function to name the image after the app's name and include a datetime stamp. The image will be saved to the app's main folder.

% Button pushed function: SnapshotButton
function SnapshotButtonPushed(app, ~) 
    % create filename containing the app's figure name (spaces removed)
    % and a datetime stamp in format yymmdd_hhmmss
    filename = sprintf('%s_%s.pdf',regexprep(app.MyApp.Name,' +',''), datestr(now(),'yymmdd_HHMMSS'));
    % Get the app's path
    filepath = fileparts(which([mfilename,'.mlapp']));
    % Store snapshot
    exportapp(app.MyApp, fullfile(filepath,filename))
end

Matlab's getframe now supports apps & uifigures

getframe(h) captures images of axes or a uifigure as a structure containing the image data which defines a movie frame. This function has been around for a while but as of r2020b , it now supports uifigures. By capturing consecutive frames, you can create a movie that can be played back within a Matlab figure (using movie ) or as an AVI file (using VideoWriter ). This is useful when demonstrating the effects of changes to app components.

The general steps to recording a process within an app as a movie are,

1. Add a button or some other event to your app that can invoke the frame recording process.

2. Animation is typically controlled by a loop with n iterations. Preallocate the structure array that will store the outputs to getframe. The example below stores the outputs within the app so that they are available by other functions within the app. That will require you to define the variable as a property in the app.

% nFrames is the number of iterations that will be recorded.
% recordedFrames is defined as a private property within the app
app.recordedFrames(1:nFrames) = struct('cdata',[],'colormap',[]);

3. Call getframe from within the loop that controls the animation. If you're using VideoWriter to create an AVI file, you'll also do that here (not shown, but see an example in the documentation ).

% app.myAppUIFigure: the app's figure handle
% getframe() also accepts axis handles
for i = 1:nFrames

      ... % code that updates the app for the next frame

      app.recordedFrames(i) = getframe(app.myAppUIFigure);
  end

4. Now the frame data are stored in app.recordedFrames and can be accessed from anywhere within the app. To play them back as a movie,

movie(app.recordedFrames) 
% or 
movie(app.recordedFrames, n) % to play the movie n-times
movie(app.recordedFrames, n, fps) % to specify the number of frames per second

To demonstrate this, I adapted a copy of Matlab's built-in PulseGenerator.mlapp by adding

• a record button
• a record status lamp with frame counter
• a playback button
• a function that animates the effects of the Edge Knob

Recording process (The GIF is a lot faster than realtime and only shows part of the recording) (Open the image in a new window or see the attached Live Script for a clearer image).

Playback process (Open the image in a new window or see the attached Live Script for a clearer image.)

Review: How to get the handle to an app figure

To use either of these functions outside of app designer, you'll need to access the App's figure handle. By default, the HandleVisibility property of uifigures is set to off preventing the use of gcf to retrieve the figure handle. Here are 4 ways to access the app's figure handle from outside of the app.

1. Store the app's handle when opening the app.

app = myApp;
% Get the figure handle
figureHandle = app.myAppUIFigure;

2. Search for the figure handle using the app's name, tag, or any other unique property value

allfigs = findall(0, 'Type', 'figure'); % handle to all existing figures
figureHandle = findall(allfigs, 'Name', 'MyApp', 'Tag', 'MyUniqueTagName');

3. Change the HandleVisibility property to on or callback so that the figure handle is accessible by gcf anywhere or from within callback functions. This can be changed programmatically or from within the app designer component browser. Note, this is not recommended since any function that uses gcf such as axes(), clf(), etc can now access your app!.

4. If the app's figure handle is needed within a callback function external to the app, you could pass the app's figure handle in as an input variable or you could use gcbf() even if the HandleVisibility is off.

See a complete list of changes to the PulseGenerator app in the attached Live Script file to recreate the app.

File Exchange now offers the ability to download/restore previous versions of community contributed files. It's often a good practice to always update your software to the latest version, however there are times when this isn't always helpful. Sometimes a software update can break or alter something you've been relying on, in these cases you'll want to stick with the version that's working for you. This is why we've added the ability to download previous versions in File Exchange.

Using Version History

Navigate to any community member file and then click the View Version History link that appears above the Download button. This will show you a list of the previous versions contributed by the submission author. Each version will have a corresponding download button, date, version number, and a description of the changes made for that update.

Let us know what you think about this new feature by replying below.

Here's a short article describing how educators from UNSW have used Live Scripts to help students understand mathematical models. Interactive live scripts allow students to experiment and understand concepts through trial and error. The article also explains how the scripts helped provide an enriched online learning experience for the students.

https://www.education.unsw.edu.au/using-matlab-live-scripts-develop-students-understanding-mathematical-models-and-analysis

Do you use Live Scripts in your teaching?

Prior to r2020b the height (number of rows) and width (number of columns) of an array or table can be determined by the size function,

array = rand(102, 16);

% Method 1
[dimensions] = size(array);
h = dimensions(1);
w = dimensions(2);

% Method 2
[h, w] = size(array); %#ok<*ASGLU>
% or
[h, ~] = size(array);
[~, w] = size(array);

% Method 3
h = size(array,1);
w = size(array,2);

In r2013b, the height(T) and width(T) functions were introduced to return the size of single dimensions for tables and timetables.

Starting in r2020b, height() and width() can be applied to arrays as an alternative to the size() function.

Continuing from the section above,

h = height(array)
% h =  102

w = width(array)
% w =  16

height() and width() can also be applied to multidimensional arrays including cell and structure arrays

mdarray = rand(4,3,20);
h = height(mdarray)
% h =  4

w = width(mdarray)
% w =  3

The expanded support of the height() and width() functions means,

1. when reading code, you can no longer assume the variable T in height(T) or width(T) refers to a table or timetable
2. greater flexibility in expressions such as the these, below

% C is a 1x4 cell array containing 4 matrices with different dimensions
rng('default')
C = {rand(5,2), rand(2,3), rand(3,4), rand(1,1)};
celldisp(C)

% C{1} =
%       0.81472      0.09754
%       0.90579       0.2785
%       0.12699      0.54688
%       0.91338      0.95751
%       0.63236      0.96489
% C{2} =
%       0.15761      0.95717      0.80028
%       0.97059      0.48538      0.14189
% C{3} =
%       0.42176      0.95949      0.84913      0.75774
%       0.91574      0.65574      0.93399      0.74313
%       0.79221     0.035712      0.67874      0.39223
% C{4} =
%       0.65548

What's the max number of rows in C?

maxRows1 = max(cellfun(@height,C))         % using height()
% maxRows1 =  5;

maxRows2 = max(cellfun(@(x)size(x,1),C))   % using size()
% maxRows2 =  5; 

What's the total number of columns in C?

totCols1 = sum(cellfun(@width,C))          % using width()
%totCols1 =  10

totCols2 = sum(cellfun(@(x)size(x,2),C))   % using size(x,2)
% totCols2 =  10

Attached is a live script containing the content of this post.

I often code snippets to students in the question description. I would like the students to be able to copy and paste these from the description into their solution, obviously all on the same web page. I thought this was the case before, but now Ctrl+C/V do not work and when I right click there is no copy/paste options. Is this not possible?

We are excited to announce that Cody Contest 2020 starts today! Again, the rule is simple - solve any problem and rate its difficulty. If you have any question, please visit our FAQs page first. Want to know your ranking? Check out the contest leaderboard .

Happy problem-solving! We hope you are a winner.