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I'm beginning this MATLAB-based numerical methods class, and as I was thinking back to my previous MATLAB/Simulink classes, I definitely remember some projects more fondly than others. One of my most memorable was where I had to use MATLAB to analyze electrocardiogram (ECG) peaks. What about you guys? What are some of the best (or worst 🤭) MATLAB projects or assignments you've been given in the past?
I have a device that via GPRS publish correctly, after autentication to the server mqtt3.thingspeak.com , a lot of datas like:
.{"sensorDatas":[{"flag":"COUNT","value":1},...........,{"flag":"AI1","value":25.80}]}
I configure a correct Channel with a field called AI1, but I can't fill it with that value 25.80.
I am sure that the device communicate to the server the string {"flag":"AI1","value":25.80} but nothing.
Could you tell me what I have to do? Probably I have to write some software code, may someone help me?
Are there some examples for a beginner like me?
Thank you very much
Ivan
Ivan
Last activity on 13 Dec 2024

Hello
I am trying to connect Thingspeak to ibfluxdb. Is that possible? how you do that??
Watt's Up with Electric Vehicles?EV modeling Ecosystem (Eco-friendly Vehicles), V2V Communication and V2I communications thereby emitting zero Emissions to considerably reduce NOx ,Particulates matters,CO2 given that Combustion is always incomplete and will always be.
Reduction of gas emissions outside to the environment will improve human life span ,few epidemic diseases and will result in long life standard
Always and almost immediately!
26%
Never
30%
After validating existing code
15%
Y'all get the new releases?
29%
1843 votes
I am using a micro:bit device with ESP8266 for a IOT project, but cannot connect thingspeak recently.
The conncection is unstable, I can hardly connect to thingspeak for days, somehow it works last night for 30 mins and then it fails.
The program does not change and I have included a 25 sec delayed between each data sending.
Please advice why and how to fix it. Thank you.
Mike Croucher
Mike Croucher
Last activity on 6 Dec 2024

Many of my best friends at MathWorks speak Spanish as their first language and we have a large community of Spanish-speaking users. You can see good evidence of this by checking out our relatively new Spanish YouTube channel which recently crossed the 10,000 subscriber mark
Mike Croucher
Mike Croucher
Last activity on 13 Dec 2024

I've always used MATLAB with other languages. In the early days, C and C++ via mex files were the most common ways I spliced two languages together. Other than that I've also used MATLAB with Java, Excel and even Fortran.
In more recent years, Python is the language I tend to use most alongside MATLAB and support for this combination is steadily improving. In my latest blog post, I show how easy it has become to use Python's Numpy with MATLAB.
Have you used this functionality much? If so, what for? How well did it work for you?
I am inspired by the latest video from YouTube science content creator Veritasium on his distinct yet thorough explanation on how rainbows work. In his video, he set up a glass sphere experiment representing how light rays would travel inside a raindrop that ultimately forms the rainbow. I highly recommend checking it out.
In the meantime, I created an interactive MATLAB App in MATLAB Online using App Designer to visualize the light paths going through a spherical raindrop with numerical calculations along the way. While I've seen many diagrams out there showing the light paths, I haven't found any doing calculations in each step. Hence I created an app in MATLAB to show the calculations along with the visualizations as one varies the position of the incoming light ray.
Demo video:
For more information about the app and how to open it and play around with it in MATLAB Online, please check out my blog article:
Our MathWorks Usability Team is working on an accessibility project and they want to interview people who use MATLAB and also have experience with screen readers.
If you fit the criteria and are interested, sign up here https://www.mathworks.com/products/usability.html?tfa_30=A11Y
I wish I knew more about the intended evolution of the capabilities of the function arguments block. I love implementing function syntaxes using this relatively new form, but it doesn't yet handle some function syntax design patterns that I think are valuable and worth keeping.
For example, some functions take an input quantity that can something numeric, or it can be an option string that descriptively names a particular value of that quantity. One example is dateshift(t,"dayofweek",dow), where dow can be an integer from 1 to 7, or it can be one of the option strings "weekday" or "weekend".
Another example is Image Processing Toolbox that take a connectivity specifier as input. The function bwconncomp is one particular case. Connectivity can be specified using certain scalars, certain arrays, or the option string "maximal".
I think this is a worthwhile function design pattern, but I don't think the arguments block validation functionality supports it well (unless you use a lot of extra code that duplicates standard MATLAB behavior, which undermines the value of the arguments block).
I posted about this today over on my blog. See "Function Syntax Design Conundrum."
MathWorkers - believe me, I know that it is not in your DNA to discuss future features. But would anyone care to offer a hint about directions for the arguments block functionality?
I am using the ELECFREAKS IOT:bit Expansion Board with micro:bit to record data, it worked normally but in this week I tested again, and discover no data is uploaded to the channel ie.no entries in channel. The code in makecode are the same as before and the wifi is work, I cannot find the reason that cause this failure.
Chuanjun
Chuanjun
Last activity on 25 Nov 2024

I am using the free option with 4 channels available. I do not have any channels listed, but when I want to create a new channel it gives me an error massage to say that I have used up my 4 channels and need to purchase units to create additional channels.
At the present time, the following problems are known in MATLAB Answers itself:
  • Symbolic output is not displaying. The work-around is to disp(char(EXPRESSION)) or pretty(EXPRESSION)
  • Symbolic preferences are sometimes set to non-defaults
Just shared an amazing YouTube video that demonstrates a real-time PID position control system using MATLAB and Arduino.
All files, including code and setup details, are available on GitHub. Check it out!
Torbjorn
Torbjorn
Last activity on 18 Nov 2024

Hello
I have 3 devices (IOT board using SIM7600 module) sending one value to Thingsspeak. Have been working just fine a couple of years. However 14/11-24 I receive http error code 406 for all 3 devices.
The http get is working just fine when testing directly in the browser (https://api.thingspeak.com/update?api_key=xxxxx&field1=33), the server return the entrie number.
However, when running the same address via SIM7600 I receive - +HTTPACTION: 0,406,0
Any tips for the 406 error code?
I don't like the change
16%
I really don't like the change
29%
I'm okay with the change
24%
I love the change
11%
I'm indifferent
11%
I want both the web & help browser
11%
38 votes

Hello, I am wondering why I have over 12000 messages (writes)per day to a channel which I only update all 8 fields every 20 minutes. Or are these statistic timely delayed? Since testing I might have more writes, but now with my ready weather station only every 20 minutes my data will be updated. Wetterbox Channel ID: 2391212 Access: Public Can you explain this to me? Thank you for your help. Regards, Julian

You can make a lot of interesting objects with matlab primitive shapes (e.g. "cylinder," "sphere," "ellipsoid") by beginning with some of the built-in Matlab primitives and simply applying deformations. The gif above demonstrates how the Manta animation was created using a cylinder as the primitive and successively applying deformations: (https://www.mathworks.com/matlabcentral/communitycontests/contests/8/entries/16252);
Similarly, last year a sphere was deformed to create a face in two of my submissions, for example, the profile in "waking":
You can piece-wise assemble images, but one of the advantages of creating objects with deformations is that you have a parametric representation of the surface. Creating a higher or lower polygon rendering of the surface is as simple as declaring the number of faces in the orignal primitive. For example here is the scene in "snowfall" using sphere with different numbers of input faces:
sphere(100)
sphere(500)
High poly models aren't always better. Low-polygon shapes can sometimes add a little distance from that low point in the uncanny valley.
Next week is MATLAB EXPO week and it will be the first one that I'm presenting at! I'll be giving two presentations, both of which are related to the intersection of MATLAB and open source software.
  • Open Source Software and MATLAB: Principles, Practices, and Python Along with MathWorks' Heather Gorr. We we discuss three different types of open source software with repsect to their relationship to MATLAB
  • The CLASSIX Story: Developing the Same Algorithm in MATLAB and Python Simultaneously A collaboration with Prof. Stefan Guettel from University of Manchester. Developing his clustering algorithm, CLASSIX, in both Python and MATLAB simulatenously helped provide insights that made the final code better than if just one language was used.
There are a ton of other great talks too. Come join us! (It's free!) MATLAB EXPO 2024