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It's pretty odd how a solution that uses more characters than usual can be the "leading solution" of a Cody problem and have the least size. Compare these two codes that find the sum of integers from 1 to 2^x, which one uses fewer characters, thus should be the better solution?
function y = sum_int(x)
regexp '' '(?@y=sum(1:2^x);)'
end
function ans = sum_int(x)
sum(1:2^x)
end
Jiro Doke
Jiro Doke
上次活动时间: 2020-8-21

Remote access robotics lab

Take a look at this video on remote access robotics lab. It allows students to submit algorithms and have them run on a robot completely remotely.

Robotarium

Here (16:56) is where the submission process is explained.

Professor Christophe Demaziere from Chalmers University of Technology, Sweden created a short course on nuclear reactor modeling.

  • The course followed a flipped and hybrid approach last year but will most likely be taught entirely online in future due to Covid-19 pandemic.
  • MATLAB Grader greatly facilitates the Online nature of Christophe's courses.
  • Student Feedback was also very positive saying that they learned better compared to the traditional approach.

More details in the article

I'm trying to list out some videos, courses, and other links to learn more about Machine and Deep Learning. Here are some links to getting started with AI/Machine Learning/Deep Learning with MATLAB:

Artificial Intelligence:

Machine Learning:

Data Analytics:

Neural Networks and Deep Learning:

If any of you are using other resources from the MathWorks website or elsewhere, please consider adding it below as a comment.

Thanks!

Hello,

I am a student. I am currently looking into graph neural networks (GNNs). My domain is electrical power systems. In electrical power systems, it is extremely important that we get an accurate desired output numerical value of electrical data from a neural network.

1) I have a basic question. Consider an electrical grid network of nodes. I am trying to learn this electrical grid network data using Graph Neural Network (GNN). Every node of a GNN accumulates data from neighboring nodes, then processes it by a few steps of an algorithm, and passes it to the next layer. Finally, data is passed through a non-linearity and then to the output layer of the GNN.

But, if I feed electrical data to the above process, the original value of data at every node gets manipulated by several processing operations, and especially after passing the manipulated data through a non-linearity at the final stage, the output is obtained only in the form of 1's and 0s. Hence, the original electrical data value at every node is totally lost. On the contrary, I am expecting an output of an "accurate" value of electrical data similar to original value electrical data at every node of the network.

How to address the above problem? Please explain systematically if possible. This is a genuine basic question.

2) Also, does anyone have a clue, why Graph Neural Networks (GNNs) have not been introduced yet as a toolbox or in general in Matlab?

Help and opinion on above questions would be greatly appreciated.

Shogo
Shogo
上次活动时间: 2020-8-21

Import csv files from folder

help

Thank you for your helping. I'm trying to import csv files form a folder, however it does not work.

The following code might be wrong.. fname=mtlb_dir('Users/shogo/Left_Leg_Single-Leg_Landing/SLLExport/*.exp')

I appreciate it if you help,

Sincerely, Shogo

This year, the 3-day MATLAB workshop is going Virtual: October 11-13 2020. (Sunday evening - Tuesday afternoon, CST). If you're teaching science, math, engineering or related disciplines, consider signing up now. The application deadline is July 31st. Apply for the workshop: Workshop Application

Details: Name: Teaching Online Computation Using MATLAB (Virtual) Date: October 11-13 2020 (Sunday afternoon -- Tuesday mid-afternoon, US time zones) Location: Zoom session Audience: Educators teaching undergraduate and graduate-level science, math, engineering and related disciplines

At the 2020 virtual workshop, you’ll have opportunities to • Curriculum: Upgrade your curriculum with a focus on transitioning to online learning • Mentoring: Meet in 1-on-1 coaching sessions with faculty, education professionals, and MATLAB experts • Publish and Cite: Get your teaching activities peer reviewed and citable for inclusion in your CV • Community: Collaborate with and build connections to a network of educator peers all working on impactful computational skill development in their courses • Learn: Learn how to embed new MATLAB tools in courses to improve student learning (Note that the workshop will use online technologies to enable 1-on-1 mentoring, group work, and community building. As in past years, the focus will be curriculum development, less presentation.)

In addition, you’ll have the chance to learn how to incorporate MATLAB Live Scripts, MATLAB Online, MATLAB Grader, and more.

This virtual will include working groups for building your curriculum. Participants will be matched with like educators.

Apply now to save your spot and help the conveners plan effective groups.

The workshop hosts will review applications and send acceptances status by early August.

Looking forward to your participation in the workshop, Cathy Manduca, Executive Director, SERC Lisa Kempler, Sponsor, MathWorks Don Baker, McGill University, workshop convener Dan Burleson, University of Houston, workshop convener and review editor Kelly Roos, Bradley University, workshop convener and reviewer Kristi Closser, California State University, Fresno, workshop convener and reviewer

P.S. For reference, 2019 workshop program

Here's an thread on comparing various types of instructional labs (on-campus, virtual, remote, kits). Each type has pros/cons and things that you need to consider.

https://twitter.com/RebeccaEE/status/1237561015350386690

Rik
Rik
上次活动时间: 2024-9-17

What frustrates you about MATLAB? #2

Similar to what has happened with the wishlist threads (#1 #2 #3 #4 #5), the "what frustrates you about MATLAB" thread has become very large. This makes navigation difficult and increases page load times.
So here is the follow-up page.
What should you post where?
Wishlist threads (#1 #2 #3 #4 #5): bugs and feature requests for Matlab Answers
Frustation threads (#1 #2): frustations 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)

Starting in r2020a , you can change the mouse pointer symbol in apps and uifigures.

The Pointer property of a figure defines the cursor’s default pointer symbol within the figure. You can also create your own pointer symbols (see part 3, below).

Part 1. How to define a default pointer symbol for a uifigure or app

For figures or uifigures, set the pointer property when you define the figure or change the pointer property using the figure handle.

% Set pointer when creating the figure
uifig = uifigure('Pointer', 'crosshair');

% Change pointer after creating the figure
uifig.Pointer = 'crosshair';

For apps made in AppDesigner, you can either set the pointer from the Design View or you can set the pointer property of the app’s UIFigure from the startup function using the second syntax shown above.

Part 2. How to change the pointer symbol dynamically

The pointer can be changed by setting specific conditions that trigger a change in the pointer symbol.

For example, the pointer can be temporarily changed to a busy-symbol when a button is pressed. This ButtonPushed callback function changes the pointer for 1 second.

function WaitasecondButtonPushed(app, event)
   % Change pointer for 1 second.
   set(app.UIFigure, 'Pointer','watch')
   pause(1)
   % Change back to default.
   set(app.UIFigure, 'Pointer','arrow')
   app.WaitasecondButton.Value = false;
end

The pointer can be changed every time it enters or leaves a uiaxes or any plotted object within the uiaxes. This is controlled by a set of pointer management functions that can be set in the app’s startup function.

iptSetPointerBehavior(obj,pointerBehavior) allows you to define what happens when the pointer enters, leaves, or moves within an object. Currently, only axes and axes objects seem to be supported for UIFigures.

iptPointerManager(hFigure,'enable') enables the figure’s pointer manager and updates it to recognize the newly added pointer behaviors.

The snippet below can be placed in the app’s startup function to change the pointer to crosshairs when the pointer enters the outerposition of a uiaxes and then change it back to the default arrow when it leaves the uiaxes.

% Define pointer behavior when pointer enter axes
pm.enterFcn = @(~,~) set(app.UIFigure, 'Pointer', 'crosshair');
pm.exitFcn  = @(~,~) set(app.UIFigure, 'Pointer', 'arrow');
pm.traverseFcn = [];
iptSetPointerBehavior(app.UIAxes, pm)

% Enable pointer manager for app
iptPointerManager(app.UIFigure,'enable');

Any function can be triggered when entering/exiting an axes object which makes the pointer management tools quite powerful. This snippet below defines a custom function cursorPositionFeedback() that responds to the pointer entering/exiting a patch object plotted within the uiaxes. When the pointer enters the patch, the patch color is changed to red, the pointer is changed to double arrows, and text appears in the app’s text area. When the pointer exits, the patch color changes back to blue, the pointer changes back to crosshairs, and the text area is cleared.

% Plot patch on uiaxes
hold(app.UIAxes, 'on')
region1 = patch(app.UIAxes,[1.5 3.5 3.5 1.5],[0 0 5 5],'b','FaceAlpha',0.07,...
    'LineWidth',2,'LineStyle','--','tag','region1');

% Define pointer behavior for patch
pm.enterFcn = @(~,~) cursorPositionFeedback(app, region1, 'in');
pm.exitFcn  = @(~,~) cursorPositionFeedback(app, region1, 'out');
pm.traverseFcn = [];
iptSetPointerBehavior(region1, pm)

% Enable pointer manager for app
iptPointerManager(app.UIFigure,'enable');

function cursorPositionFeedback(app, hobj, inout)
% When inout is 'in', change hobj facecolor to red and update textbox.
% When inout is 'out' change hobj facecolor to blue, and clear textbox.
% Check tag property of hobj to identify the object.
switch lower(inout)
    case 'in'
        facecolor = 'r';
        txt = 'Inside region 1';
        pointer = 'fleur';
    case 'out'
        facecolor = 'b';
        txt = '';
        pointer = 'crosshair';
end
hobj.FaceColor = facecolor;
app.TextArea.Value = txt;
set(app.UIFigure, 'Pointer', pointer)
end

The app showing the demo below is attached.

Part 3. Create your own custom pointer symbol

  1. Set the figure’s pointer property to ‘custom’.
  2. Set the figure’s PointerShapeCData property to the custom pointer matrix. A custom pointer is defined by a 16x16 or 32x32 matrix where NaN values are transparent, 1=black, and 2=white.
  3. Set the figure’s PointerShapeHotSpot to [m,n] where m and n are the coordinates that define the tip or "hotspot" of the matrix.

This demo uses the attached mat file to create a black hand pointer symbol.

iconData = load('blackHandPointer.mat');
uifig = uifigure(); 
uifig.Pointer = 'custom'; 
uifig.PointerShapeCData = iconData.blackHandIcon; 
uifig.PointerShapeHotSpot = iconData.hotspot;

Also see Jiro's pointereditor() function on the file exchange which allows you to draw your own pointer.

As an environment for modeling, simulating, and testing dynamic systems, Simulink is used for:

Simulink is now available in a web browser as Simulink Online.

Simulink Online is available to anyone with access to MATLAB Online (see supported license types here) and a Simulink license.

Just sign into MATLAB Online and either start Simulink or open a Simulink model.

Learn more about Simulink Online at the product page on our website.

Simulink Online currently supports the following toolboxes, with more to be added in the future!

  • Simulink
  • Stateflow
  • Simscape
  • Simscape Electrical
  • Simscape Multibody
  • Simulink Control Design
  • DSP System Toolbox

MathWorks gave a perspective on 'Bridging the Technology Readiness Gap with Simulation and Virtual/Remote Testbenches' at the Opal-RT RT20 Panel Session on The Role of Real-Time Simulation in Education. Listen to a recording of the panel session, and also hear perspectives from Quanser, Hydro-Quebec, and RWTH Aachen, by registering for the RT20 conference at the following link .

The EMEA (Europe, Middle East and Africa) Academic Engineering Team are hosting a series of live online webinars every Tuesday and Wednesday. Get up to speed with online teaching and research with MATLAB and access ready-to-use resources.

Watch the introductory video and register here

Where is very courses and how to catch the courses

Div Tiwari
Div Tiwari
上次活动时间: 2020-8-21

Moving Lab-based Classes Online

In this article, we discuss how educators can adopt simulation, alternative hardware, and other teaching resources to transition lab-based classes to distance learning: https://medium.com/mathworks/tips-for-moving-your-lab-based-classes-online-1cb53e90ee00.

Do you teach a lab-based class? Please share your thoughts, questions, experience, and feedback on these ideas here. I also welcome you to invite your colleagues to join the discussion here.

One community within MathWorks that has been helping students continue their learning is MATLAB Student Ambassadors. Despite new challenges with transitioning to distance learning, student ambassadors have done a truly amazing job. In a blog that was published recently, I discuss 3 examples of the great things that our student ambassadors have done to aid distance learning. Click here to read the blog. I hope after reading this blog you share my level of admiration for these students.

Student Ambassador at University of Houston hosting a fun and informative virtual event.

We are excited to announce that File Exchange now awards reputation points to the authors and you can view the points and rankings by week, month, year or all-time on the new leaderboard .
Reputation point is commonly used in many online communities to build trust and show appreciation to contributors. File Exchange rewards reputation points to authors who submit files, but it's definitely not easy to earn! You earn points when your files are downloaded or rated by other community members. Therefore, you should be very proud of yourself no matter you have 10 points or 10,000 points. It's the recognition from the community. See table below for detailed rules:
Now that we have reputation points on File Exchange, we introduced the short-term leaderboard to better view the points and rankings. You can filter by 7-day, 30-day, 365-day, and all-time, which helps you understand who is more active recently or who is a long-time contributor.
We hope the reputation and new leaderboard will contribute to the growth and success of File Exchange community. Your feedback is extremely valuable to us. Simply reply to this article if you have any questions, comments, or suggestions.
Chen Lin
Chen Lin
上次活动时间: 2020-5-11

User Spotlight: Rik

Today, I'm spotlighting Rik, our newest and the 31st MVP in MATLAB Answers. Two weeks ago, we just celebrated Ameer Hamza for reaching the MVP milestone. Today, we are thrilled that we have another new MVP!

Since his first answer in Feb 2017, Rik has been contributing high-quality answers every quarter!

Besides those high-quality answers, Rik so far has submitted 21 files to File Exchange, one of which was chosen by MathWorks as the 'Pick of the Week'. Check the shining badge below.

Congratulations Rik! Thank you for your hard work and outstanding contributions.

hi how to apply single stream into multiple channels in fft simulink simulation from workspace