Results for
We are thrilled to see the incredible short movies created during Week 3. The bar has been set exceptionally high! This week, we invited our Community Advisory Board (CAB) members to select winners. Here are their picks:
Mini Hack Winners - Week 3
Game:
Holidays:
Fractals:
Realism:
Great Remixes:
Seamless loop:
Fun:
Weekly Special Prizes
Thank you for sharing your tips & tricks with the community. You won a limited-edition MATLAB Shorts.

We still have plenty of MATLAB Shorts available, so be sure to create your posts before the contest ends. Don't miss out on the opportunity to showcase your creativity!
Hi,
I don't know why really. Why is there seems a difference between daily average that calculated with .csv file that has exported directly from the channel.
and calculation with the ThingSpeak Daily Average API, there is a lot of difference at the moment.
Why does this happens, and how should I fix this issue?
Attached image file is daily average that has been retrived through the API,
And attached excel file is raw data from the channel.
Thank you.



Just in two weeks, we already have 150+ entries! We are so impressed by your creative styles, artistic talents, and ingenious programming techniques.
Now, it’s time to announce the weekly winners!
Mini Hack Winners - Week 2
Seamless loop:
Nature & Animals:
Game:
Synchrony:
Remix of previous Mini Hack entries
Movie:
Congratulations to all winners! Each of you won your choice of a T-shirt, a hat, or a coffee mug. We will contact you after the contest ends.
In week 3, we’d love to see and award entries in the ‘holiday’ category.
Weekly Special Prizes
Thank you for sharing your tips & tricks with the community. You won limited-edition MATLAB Shorts.
We highly encourage everyone to share various types of content, such as tips and tricks for creating animations, background stories of your entry, or learnings you've gained from the contest.
Hello! The MathWorks Book Program is thrilled to welcome you to our discussion channel dedicated to books on MATLAB and Simulink. Here, you can:
- Promote Your Books: Are you an author of a book on MATLAB or Simulink? Feel free to share your work with our community. We’re eager to learn about your insights and contributions to the field.
- Request Recommendations: Looking for a book on a specific topic? Whether you're diving into advanced simulations or just starting with MATLAB, our community is here to help you find the perfect read.
- Ask Questions: Curious about the MathWorks Book Program, or need guidance on finding resources? Post your questions and let our knowledgeable community assist you.
We’re excited to see the discussions and exchanges that will unfold here. Whether you're an expert or beginner, there's a place for you in our community. Let's embark on this journey together!
My Licensed avvount has expired. When I go to my expired license page, I select "Revert To Free Account", I get the following message:
Only administrators of this license are allowed to renew units on this ThingSpeak license. If you want to continue to collect data in your ThingSpeak channels, contact your license administrator.
Aren't I the license administrator? or do I need to contact someone at Thingspeak/MathWorks?
There are so many incredible entries created in week 1. Now, it’s time to announce the weekly winners in various categories!
Nature & Space:
Seamless Loop:
Abstract:
Remix of previous Mini Hack entries:
Early Discovery
Holiday:
Congratulations to all winners! Each of you won your choice of a T-shirt, a hat, or a coffee mug. We will contact you after the contest ends.
In week 2, we’d love to see and award more entries in the ‘Seamless Loop’ category. We can't wait to see your creativity shine!
Tips for Week 2:
1.Use AI for assistance
The code from the Mini Hack entries can be challenging, even for experienced MATLAB users. Utilize AI tools for MATLAB to help you understand the code and modify the code. Here is an example of a remix assisted by AI. @Hans Scharler used MATLAB GPT to get an explanation of the code and then prompted it to ‘change the background to a starry night with the moon.’
2. Share your thoughts
Share your tips & tricks, experience of using AI, or learnings with the community. Post your knowledge in the Discussions' general channel (be sure to add the tag 'contest2024') to earn opportunities to win the coveted MATLAB Shorts.
3. Ensure Thumbnails Are Displayed:
You might have noticed that some entries on the leaderboard lack a thumbnail image. To fix this, ensure you include ‘drawframe(1)’ in your code.
Over the past week, we have seen many creative and compelling short movies! Now, let the voting begin! Cast your votes for the short movies you love. Authors, share your creations with friends, classmates, and colleagues. Let's showcase the beauty of mathematics to the world!
We know that one of the key goals for joining the Mini Hack contest is to LEARN! To celebrate knowledge sharing, we have special prizes—limited-edition MATLAB Shorts—up for grabs!

These exclusive prizes can only be earned through the MATLAB Shorts Mini Hack contest. Interested? Share your knowledge in the Discussions' general channel (be sure to add the tag 'contest2024') to earn opportunities to win the coveted MATLAB Shorts. You can share various types of content, such as tips and tricks for creating animations, background stories of your entry, or learnings you've gained from the contest. We will select different types of winners each week.

We also have an exciting feature announcement: you can now experiment with code in MATLAB Online. Simply click the 'Open in MATLAB Online' button above the movie preview section. Even better! ‘Open in MATLAB Online’ is also available in previous Mini Hack contests!

We look forward to seeing more amazing short movies in Week 2!
We're excited to announce that the 2024 Community Contest—MATLAB Shorts Mini Hack starts today! The contest will run for 5 weeks, from Oct. 7th to Nov. 10th.
What creative short movies will you create? Let the party begin, and we look forward to seeing you all in the contest!
Hi, My data send to thingspeak is not received/updated for the last 6 hours on the charts and dials. All worked well till about 6 hour ago. I am using Node-red and the API Url: https://thingspeak.com
Any help please?
Greetings Gert
To solve issues around the browsers blocking 3p cookies and having different behavior across different browsers, the ThingSpeak website is now served from https://thingspeak.mathworks.com. There are no changes required from devices or users. Just log in and use the service as you always did.
I left the code unchanged, modifying only secrets.h.
I am using an ESP32-WROOM -32U
Connection to network succeeds, but ThingSpeak.writeFields fails every time, with HTTP error code 400.
The sketch I am really trying to use is loosely based on this example, accesses Time and Weather info with no problems, but ThingSpeak.writeFields fails with HTTP error code 301.
This is my first attempt to use ThingSpeak.
Is this example sketch still valid, or must I look elsewhere? Suggestions please.
Dear contest participants,
The 2024 Community Contest—MATLAB Shorts Mini Hack—is just one week away! Last year, we challenged you to create a 48-frame, 2-second animation. This year, we're doubling the fun by increasing the frame count to 96 and adding audio support. Your mission? Create a short movie!
As always, whether you are a seasoned MATLAB user or just a beginner, you can participate in the contest and have opportunities to win amazing prizes.

Timeframe:
- The contest will run for 5 weeks, from Oct. 7th to Nov. 10th, Eastern Time.
General Rules:
- The first week is dedicated to entry creation, and the fifth week is reserved for voting only.
- Create a 96-frame, 4-second animation and add audio. We will loop it 3 times to create a 12-second short movie for you.
- The character limit remains at 2,000 characters.
Prizes
- You will have opportunities to win compelling prizes, including Amazon gift cards, MathWorks T-shirts, and virtual badges. We will give out both weekly prizes and grand prizes.
Warm-up!
With one week left before the contest begins, we recommend you warm up by reading a fantastic article: Walkthrough: making Little Nemo's airship in MATLAB by @Tim. The article shares both technical insights and the challenges encountered along the way.
The MATLAB Central Community Team
Hi everyone,
I'm working on a school project where I need to send sensor data from my Arduino to a Power BI REST API using ThingsHTTP. I've been trying to get this to work, but I'm running into errors like this:
{"error":{"code":"InvalidRequest","message":"Error parsing request for dataset sobe_wowvirtualserver|a7b68fb5-533b-471f-a5da-3bdd6746ee16: Conversion error on column '<pi>pH</pi>': <pi>Input string was not in a correct format.</pi>"}}
I'm a beginner with this, and I'm not sure what I'm doing wrong. What steps should I take to resolve this issue? Also, does anyone know the correct format for an HTTP request body when sending dynamic sensor data?
This is the body format I'm trying to send to Power BI:
[
{
"pH": 98.6,
"TDS": 98.6,
"turbidity": 98.6,
"temperature": 98.6
}
]
Any advice on how to construct the HTTP body with values that change over time would be greatly appreciated! Thanks in advance!"
hope this message finds you well. I am currently working on a project involving the design and numerical simulation of metalenses using Zemax and MATLAB. The design phase involves saving phase data from the Zemax simulation, which is later used in a numerical script to generate the metalens in MATLAB.
I have a MATLAB file that contains the phase data saved from Zemax, but I am unsure of the specific method or format used to extract and save the data from Zemax. The phase data I currently have in MATLAB is as follows:
- Phase matrix: 571 x 571 (double)
- X data: 571 x 1 (double)
- Y data: 571 x 1 (double)
Could you please provide guidance on:
- How this phase data was likely saved from Zemax into MATLAB?
- What steps or scripts were used to extract this information from the design, particularly the 571 x 571 phase matrix and the corresponding X and Y data?
- Any best practices or tools available in Zemax for exporting such data?
This information will help me reproduce the workflow and proceed with my analysis.
Thank you for your support. I look forward to your guidance.
Best regards,
Zaka
I went to perform an IoT for an automated plantation but the same error always occurs to me when I upload it to the mcu node, which is: Connection to ThingSpeak failed.
Dear MATLAB contest enthusiasts,
In the 2023 MATLAB Mini Hack Contest, Tim Marston captivated everyone with his incredible animations, showcasing both creativity and skill, ultimately earning him the 1st prize.
We had the pleasure of interviewing Tim to delve into his inspiring story. You can read the full interview on MathWorks Blogs: Community Q&A – Tim Marston.
Last question: Are you ready for this year’s Mini Hack contest?
It's been over six years since I've written any serious MATLAB code, so I thought it would be fun to see how easily ChatGPT could help me out. While others have probably already used ChatGPT to generate MATLAB code, I didn't find any evidence of it when I searched through the ThingSpeak forum. That inspired me to post an example to get people thinking about it.
This example reads four temperature fields from the same channel and plots them on a single graph.
My ChatGPT prompt:
The prompt is pretty straightforward and essentially walks through all the elements of the chart that I wanted. It's also important to consider any filtering or "data cleansing" that should be done. Since this was my first time doing this, I decided to use an existing plot I was already familiar with as my "target state".
The prompt: "I would like you to generate some MATLAB code to create what is called a MATLAB Visualization. Its purpose will be to generate a chart of 4 fields found in a ThingSpeak channel. The ThingSpeak channel name is "Nest Nanny 2 (NN-02)" and its channel id (needed for the code) is xxxxxxx. The read api key is XXXXXXXXXXXXXXXX. The chart title should be "Nest Nanny 02 (NN-02) Todays Temperature Readings" It should plot data from 4 fields (field 3 - 6) who's names are "Surface Temp", "1/4 Temp", "3/4 Temp", and "Deep Temp". I would like the plot lines for these 4 fields to be different colors (red, orange, cyan, and blue) but on the same chart. I would like Temperature in Fahrenheit to be on the Y axis and Time on the x axis. I would like it to display the last 100 data points. I'd like to use this colororder. colororder(["#FF0000","#FFBB00","#00BBFF", "#0000FF"]) I would like the legend to be to the right of the chart, not contained within the chart. No temperature data should have a value of 50 or less and we can assume it's a sensor issue when this is observed. If a data value is 50 or less, use the value of it's nearest (in the time series) non-zero, non-negative value for that field. The data is stored in the channel as Fahrenheit and does not need to be converted from Celsius. "
Because I did this exercise using an existing plot and had a clear objective in mind, it was relatively quick to iterate four or five times with ChatGPT to refine my prompt. In just a few minutes, the generated plot almost perfectly matched my existing plot. (I xxxx'ed out the channel ID and API key before posting.) For someone who now only occasionally uses MATLAB, this approach saves time and will hopefully allow me to tap into elements of MATLAB that are now beyond my skill level and memory. ;)
ChatGPT generated MATLAB code:
% MATLAB code to create a ThingSpeak Visualization for temperature readings
% Define channel ID and Read API Key
channelID = xxxxxxx;
readAPIKey = 'XXXXXXXXXXXXXXXX';
% Number of data points to retrieve
numPoints = 100;
% Read data from the ThingSpeak channel for fields 3 to 6
[data, time] = thingSpeakRead(channelID, ...
'Fields', [3 4 5 6], ...
'NumPoints', numPoints, ...
'ReadKey', readAPIKey);
% Replace any value 50 or less with the nearest non-zero, non-negative value
for i = 1:size(data, 2)
% Identify indices where the data is 50 or less
badIndices = find(data(:,i) <= 50);
% Identify indices where the data is valid (greater than 50)
validIndices = find(data(:,i) > 50);
% Interpolate to replace bad values
if ~isempty(validIndices)
data(badIndices, i) = interp1(validIndices, data(validIndices, i), badIndices, 'linear', 'extrap');
end
end
% Plot the data
figure;
colororder(["#FF0000","#FFBB00","#00BBFF", "#0000FF"]); % Set the color order
plot(time, data(:,1), 'LineWidth', 2); hold on;
plot(time, data(:,2), 'LineWidth', 2);
plot(time, data(:,3), 'LineWidth', 2);
plot(time, data(:,4), 'LineWidth', 2);
hold off;
% Add labels and title
xlabel('Time');
ylabel('Temperature (°F)');
title('Nest Nanny 02 (NN-02) Todays Temperature Readings');
% Add legend and move it to the right of the chart
legend({'Surface Temp', '1/4 Temp', '3/4 Temp', 'Deep Temp'}, ...
'Location', 'eastoutside');
% Format the time on the x-axis
datetick('x', 'HH:MM:SS', 'keepticks');
grid on;
% Adjust the figure for better readability
set(gca, 'FontSize', 12);
Plot Comparison:

I am creating an ESP32 device which will upload data to thingspeak channel and I want the data to be displayed on my website after login. I have succesfully completed the first part of uploading the data to thingspeak. Any suggestions with second part will be very much appreciated.
Hi,
I tried several times to clear my channel data.
I would expect, when I click on Channel settings-clear channel all data from the channel is gone.
For me the data stay in. Delete channel works fine.
Is there a trick?
many thanks for your help
HEP
I'm almost embarressed enough to not ask this. :) I assumed sorting the "Updated" column in the "My Channels" view would sort my channels based on when data was last written to (last updated to) the channel
However, I have channels that have received date in August and yet the date/time stamp in the Uodated column displays a June date and therefore they sort in the wrong order. Does "update" mean something other than a data update, such as a settings update? If so, if there a way to sort the channels by the more recent data update?