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Chen Lin
Last activity 2024 年 6 月 9 日

🌿🐑 Meet MATLAMB 🐑🌿

Drumlin Farm has welcomed MATLAMB, named in honor of MathWorks, among ten adorable new lambs this season!

matlamb

Books

Oge Marques
Last activity 2024 年 10 月 29 日 19:26

New book announcement: "Image Processing Recipes in MATLAB"

📚 New Book Announcement: "Image Processing Recipes in MATLAB" 📚

I am delighted to share the release of my latest book, "Image Processing Recipes in MATLAB," co-authored by my dear friend and colleague Gustavo Benvenutti Borba.

This 'cookbook' contains 30 practical recipes for image processing, ranging from foundational techniques to recently published algorithms. It serves as a concise and readable reference for quickly and efficiently deploying image processing pipelines in MATLAB.

Gustavo and I are immensely grateful to the MathWorks Book Program for their support. We also want to thank Randi Slack and her fantastic team at CRC Press for their patience, expertise, and professionalism throughout the process.

___________

Hans Scharler
Last activity 2024 年 5 月 17 日

The Office Words Spoken by Episode

I found this plot of words said by different characters on the US version of The Office sitcom. There's a sparkline for each character from pilot to finale episode.

lazymatlab
Last activity 2024 年 5 月 18 日

Helped a high school student for a physics problem with this.

A high school student called for help with this physics problem:

Car A moves with constant velocity v.
Car B starts to move when Car A passes through the point P.
Car B undergoes...
uniform acc. motion from P to Q.
uniform velocity motion from Q to R.
uniform acc. motion from R to S.
Car A and B pass through the point R simultaneously.
Car A and B arrive at the point S simultaneously.

Q1. When car A passes the point Q, which is moving faster?

Q2. Solve the time duration for car B to move from P to Q using L and v.

Q3. Magnitude of acc. of car B from P to Q, and from R to S: which is bigger?

Well, it can be solved with a series of tedious equations. But... how about this?

Code below:

%% get images and prepare stuffs
figure(WindowStyle="docked"), 
ax1 = subplot(2,1,1);
hold on, box on
ax1.XTick = [];
ax1.YTick = [];
A = plot(0, 1, 'ro', MarkerSize=10, MarkerFaceColor='r');
B = plot(0, 0, 'bo', MarkerSize=10, MarkerFaceColor='b');
[carA, ~, alphaA] = imread('https://cdn.pixabay.com/photo/2013/07/12/11/58/car-145008_960_720.png');
[carB, ~, alphaB] = imread('https://cdn.pixabay.com/photo/2014/04/03/10/54/car-311712_960_720.png');
carA = imrotate(imresize(carA, 0.1), -90);
carB = imrotate(imresize(carB, 0.1), 180);
alphaA = imrotate(imresize(alphaA, 0.1), -90);
alphaB = imrotate(imresize(alphaB, 0.1), 180);
carA = imagesc(carA, AlphaData=alphaA, XData=[-0.1, 0.1], YData=[0.9, 1.1]);
carB = imagesc(carB, AlphaData=alphaB, XData=[-0.1, 0.1], YData=[-0.1, 0.1]);
txtA = text(0, 0.85, 'A', FontSize=12);
txtB = text(0, 0.17, 'B', FontSize=12);
yline(1, 'r--')
yline(0, 'b--')
xline(1, 'k--')
xline(2, 'k--')
text(1, -0.2, 'Q', FontSize=20, HorizontalAlignment='center')
text(2, -0.2, 'R', FontSize=20, HorizontalAlignment='center')
% legend('A', 'B') % this make the animation slow. why?
xlim([0, 3])
ylim([-.3, 1.3])
%% axes2: plots velocity graph
ax2 = subplot(2,1,2);
box on, hold on
xlabel('t'), ylabel('v')
vA = plot(0, 1, 'r.-');
vB = plot(0, 0, 'b.-');
xline(1, 'k--')
xline(2, 'k--')
xlim([0, 3])
ylim([-.3, 1.8])
p1 = patch([0, 0, 0, 0], [0, 1, 1, 0], [248, 209, 188]/255, ...
    EdgeColor = 'none', ...
    FaceAlpha = 0.3);
%% solution
v = 1; % car A moves with constant speed.
L = 1; % distances of P-Q, Q-R, R-S
% acc. of car B for three intervals
a(1) = 9*v^2/8/L;
a(2) = 0;
a(3) = -1;
t_BatQ = sqrt(2*L/a(1)); % time when car B arrives at Q
v_B2 = a(1) * t_BatQ; % speed of car B between Q-R
%% patches for velocity graph
p2 = patch([t_BatQ, t_BatQ, t_BatQ, t_BatQ], [1, 1, v_B2, v_B2], ...
    [248, 209, 188]/255, ...
    EdgeColor = 'none', ...
    FaceAlpha = 0.3);
p3 = patch([2, 2, 2, 2], [1, v_B2, v_B2, 1], [194, 234, 179]/255, ...
    EdgeColor = 'none', ...
    FaceAlpha = 0.3);
%% animation
tt = linspace(0, 3, 2000);
for t = tt
    A.XData = v * t;
    vA.XData = [vA.XData, t];
    vA.YData = [vA.YData, 1];
    if t < t_BatQ
        B.XData = 1/2 * a(1) * t^2;
        vB.XData = [vB.XData, t];
        vB.YData = [vB.YData, a(1) * t];
        p1.XData = [0, t, t, 0];
        p1.YData = [0, vB.YData(end), 1, 1];
    elseif t >= t_BatQ && t < 2
        B.XData = L + (t - t_BatQ) * v_B2;
        vB.XData = [vB.XData, t];
        vB.YData = [vB.YData, v_B2];
        p2.XData = [t_BatQ, t, t, t_BatQ];
        p2.YData = [1, 1, vB.YData(end), vB.YData(end)];
    else
        B.XData = 2*L + v_B2 * (t - 2) + 1/2 * a(3) * (t-2)^2;
        vB.XData = [vB.XData, t];
        vB.YData = [vB.YData, v_B2 + a(3) * (t - 2)];
        p3.XData = [2, t, t, 2];
        p3.YData = [1, 1, vB.YData(end), v_B2];
    end
    txtA.Position(1) = A.XData(end);
    txtB.Position(1) = B.XData(end);
    carA.XData = A.XData(end) + [-.1, .1];
    carB.XData = B.XData(end) + [-.1, .1];
    drawnow
end

Mathew
Last activity 2024 年 5 月 16 日

Any helpful link

is there any sites available online free ai course learning except: coursera.org

Off Topic

Chen Lin
Last activity 2024 年 7 月 3 日

Northern Lights

Northern lights captured from this weekend at MathWorks campus ✨

Did you get a chance to see lights and take some photos?

Contests

Chen Lin
Last activity 2024 年 5 月 9 日

Unveiling Creativity: An Interview with Zhaoxu Liu / slanderer

Dear MATLAB contest enthusiasts,

I believe many of you have been captivated by the innovative entries from Zhaoxu Liu / slanderer, in the 2023 MATLAB Flipbook Mini Hack contest.

Ever wondered about the person behind these creative entries? What drives a MATLAB user to such levels of skill? And what inspired his participation in the contest? We were just as curious as you are!

We were delighted to catch up with him and learn more about his use of MATLAB. The interview has recently been published in MathWorks Blogs. For an in-depth look into his insights and experiences, be sure to read our latest blog post: Community Q&A – Zhaoxu Liu.

But the conversation doesn't end here! Who would you like to see featured in our next interview? Drop their name in the comments section below and let us know who we should reach out to next!

Gregory Vernon
Last activity 2024 年 5 月 6 日

Support "hidden blocks" in Livescripts

Updating some of my educational Livescripts to 2024a, really love the new "define a function anywhere" feature, and have a "new" idea for improving Livescripts -- support "hidden" code blocks similar to the Jupyter Notebooks functionality.

For example, I often create "complicated" plots with a bunch of ancillary items and I don't want this code exposed to the reader by default, as it might confuse the reader. For example, consider a Livescript that might read like this:

-----

Noting the similar structure of these two mappings, let's now write a function that simply maps from some domain to some other domain using change of variable.

function x = ChangeOfVariable( x, from_domain, to_domain )
x = x - from_domain(1);
x = x * ( ( to_domain(2) - to_domain(1) ) / ( from_domain(2) - from_domain(1) ) );
x = x + to_domain(1);
end

Let's see this function in action

% HIDE CELL
clear
close all

from_domain = [-1, 1];
to_domain = [2, 7];
from_values = [-1, -0.5, 0, 0.5, 1];
to_values = ChangeOfVariable( from_values, from_domain, to_domain )

to_values = 1×5

2.0000 3.2500 4.5000 5.7500 7.0000

We can plot the values of from_values and to_values, showing how they're connected to each other:

% HIDE CELL
figure
hold on
for n = 1 : 5
    plot( [from_values(n) to_values(n)], [1 0], Color="k", LineWidth=1 )
end
ax = gca;
ax.YTick = [];
ax.XLim = [ min( [from_domain, to_domain] ) - 1,  max( [from_domain, to_domain] ) + 1 ];
ax.YLim = [-0.5, 1.5];
ax.XGrid = "on";
scatter( from_values, ones( 5, 1 ), Marker="s", MarkerFaceColor="flat", MarkerEdgeColor="k", SizeData=120, LineWidth=1, SeriesIndex=1 )
text( mean( from_domain ), 1.25, "$\xi$", Interpreter="latex", HorizontalAlignment="center", VerticalAlignment="middle" )
scatter( to_values, zeros( 5, 1 ), Marker="o", MarkerFaceColor="flat", MarkerEdgeColor="k", SizeData=120, LineWidth=1, SeriesIndex=2 )
text( mean( to_domain ), -0.25, "$x$", Interpreter="latex", HorizontalAlignment="center", VerticalAlignment="middle" )
scaled_arrow( ax, [mean( [from_domain(1), to_domain(1) ] ) - 1, 0.5], ( 1 - 0 ) / ( from_domain(1) - to_domain(1) ), 1 )
scaled_arrow( ax, [mean( [from_domain(end), to_domain(end)] ) + 1, 0.5], ( 1 - 0 ) / ( from_domain(end) - to_domain(end) ), -1 )
text( mean( [from_domain(1), to_domain(1) ] ) - 1.5, 0.5, "$x(\xi)$", Interpreter="latex", HorizontalAlignment="center", VerticalAlignment="middle" )
text( mean( [from_domain(end), to_domain(end)] ) + 1.5, 0.5, "$\xi(x)$", Interpreter="latex", HorizontalAlignment="center", VerticalAlignment="middle" )

-----

Where scaled_arrow is some utility function I've defined elsewhere... See how a majority of the code is simply "drivel" to create the plot, clear and close? I'd like to be able to hide those cells so that it would look more like this:

-----

Noting the similar structure of these two mappings, let's now write a function that simply maps from some domain to some other domain using change of variable.

function x = ChangeOfVariable( x, from_domain, to_domain )
x = x - from_domain(1);
x = x * ( ( to_domain(2) - to_domain(1) ) / ( from_domain(2) - from_domain(1) ) );
x = x + to_domain(1);
end

Let's see this function in action

▶ Show code cell

from_domain = [-1, 1];
to_domain = [2, 7];
from_values = [-1, -0.5, 0, 0.5, 1];
to_values = ChangeOfVariable( from_values, from_domain, to_domain )

to_values = 1×5

2.0000 3.2500 4.5000 5.7500 7.0000

We can plot the values of from_values and to_values, showing how they're connected to each other:

▶ Show code cell

-----

Thoughts?

Emma Farnan
Last activity 2024 年 5 月 6 日

Include information about the "Margin" toggles in Preferences

I recently had issues with code folding seeming to disappear and it turns out that I had unknowingly disabled the "show code folding margin" option by accident. Despite using MATLAB for several years, I had no idea this was an option, especially since there seemed to be no references to it in the code folding part of the "Preferences" menu.

It would be great if in the future, there was a warning that told you about this when you try enable/disable folding in the Preferences.

I am using 2023b by the way.

Jérôme
Last activity 2024 年 4 月 29 日

Highlighting structure fields in MATLAB editor

In the MATLAB editor, when clicking on a variable name, all the other instances of the variable name will be highlighted.

But this does not work for structure fields, which is a pity. Such feature would be quite often useful for me.

I show an illustration below, and compare it with Visual Studio Code that does it. ;-)

I am using MATLAB R2023a, sorry if it has been added to newer versions, but I didn't see it in the release notes.

Mike
Last activity 2024 年 5 月 31 日

Research ethics using generative A.I

Dear members, I’m currently doing research on the subject of using Generative A.I. as a digital designer. What our research group would like to know is which ethical issues have a big impact on the decisions you guys and girls make using generative A.I.

Whether you’re using A.I. or not, we would really like to know your vision and opinion about this subject. Please empty your thoughts and oppinion into your answers, we would like to get as much information as possible.

Are you currently using A.I. when doing your job? Yes, what for. No (not yet), why not?

Using A.I., would you use real information or alter names/numbers to get an answer?

What information would or wouldn’t you use? If the client is asking/ordering you to do certain things that go against your principles, would you still do it because order is order? How far would you go?

Who is responsible for the outcome of the generated content, you or the client?

Would you still feel like a product owner if it was co-developed with A.I.?

What we are looking for is that we would like to know why people do or don’t use AI in the field of design and wich ethical considerations they make. We’re just looking for general moral line of people, for example: 70% of designers don’t feel owner of a design that is generated by AI but 95% feels owner when it is co-created.

So therefore the questions we asked, we want to know the how you feel about this.

https://sherwood.news/tech/how-do-ai-models-stack-up-vs-humans-on-standardized-benchmarks/

David
Last activity 2024 年 4 月 18 日

AI Models Are Improving Every Year

How long until the 'dumbest' models are smarter than your average person? Thanks for sharing this article @Adam Danz

Off Topic

Athanasios Paraskevopoulos
Last activity 2024 年 7 月 27 日

Seeking Contributors for Upcoming Book on Matrix Algebra with MATLAB for Undergraduate Students

Hello MathWorks Community,

I am excited to announce that I am currently working on a book project centered around Matrix Algebra, specifically designed for MATLAB users. This book aims to cater to undergraduate students in engineering, where Matrix Algebra serves as a foundational element.

Matrix Algebra is not only pivotal in understanding complex engineering concepts but also in applying these principles effectively in various technological solutions. MATLAB, renowned for its powerful computational capabilities, is an excellent tool to explore and implement these concepts, making it a perfect companion for this book.

As I embark on this journey to create a resource that bridges theoretical matrix algebra with practical MATLAB applications, I am looking for one or two knowledgeable individuals who have a firm grasp of both subjects. If you have experience in teaching or applying matrix algebra in engineering contexts and are familiar with MATLAB, your contribution could be invaluable.

Collaborators will help in shaping the content to ensure it is educational, engaging, and technically robust, making complex concepts accessible and applicable for students.

If you are interested in contributing to this project or know someone who might be, please reach out to discuss how we can work together to make this book a valuable resource for engineering students.

Thank you and looking forward to your participation!

Athanasios Paraskevopoulos
Last activity 2024 年 4 月 14 日

How do mathematicians walk their dogs?

What's your way?

Vonny Groose
Last activity 2024 年 11 月 8 日 21:03

Pet Day with PetWorks photo contest

Mari is helping Dad work.

Tom Sleeper
Last activity 2024 年 6 月 9 日

#nationalpetday Tucker (a.k.a Tuckaroo) never ceases to amaze me

Today, he got dressed for work to design some new dog toy-making algorithms. #nationalpetday

RAGHUVEER RAJESH
Last activity 2024 年 4 月 11 日

Paws and Pixels: Image Processing using PETLAB..Sorry MATLAB

Transforming my furry friend into a grayscale masterpiece with MATLAB! 🐾 #MATLABPetsDay ✌️

Hans Scharler
Last activity 2024 年 4 月 11 日

Stella while compiling the project...

This is Stella while waiting to see if the code works...

Off Topic

Chen Lin
Last activity 2024 年 4 月 12 日

Spring is on the way!

What's the weather like in your place?