結果:
i have imported data from a chanel, edited it and re uploaded again,
it returns error message when i upload it.
it says "The uploaded file was not imported because it is empty"
Mathworks returns also a message to my email saying "Timestamp already in channel."
Hello,
Can someone please give me a hint how the settings at Tasmoto have to be made in order to send data via MQTT to ThingSpeak.
Halil Kemal has an open channel tag: tasmota where this seems to work.
Thank you in advance for your support.
TOM
4 weeks of contests is fun but intense. Next, we recommend 3 things to do as warm-down exercises.
To make future contests better and more appealing to you, we created a 1-minute survey to understand your experience. Your feedback is critical to us!
Dave Bulkin is a developer on the MATLAB Graphics and Charting Team. In the Blog post, @Dave B not only examines the code behind the leading entries, but also introduces you to some new visualization techniques.
Matt Tearle is from MathWorks Training Services Team. @Matt Tearle created this problem group to celebrate the 10th anniversary of Cody and the 2022 T20 World Cup (which happened to occur at the same time). Note that the problems can be done without the knowledge of cricket.
Thank you in advance and hope to see you in 2023!
I've now seen linear programming questions pop up on Answers recently, with some common failure modes for linprog that people seem not to understand.
One basic failure mode is an infeasible problem. What does this mean, and can it be resolved?
The most common failure mode seems to be a unbounded problem. What does this mean? How can it be avoided/solved/fixed? Is there some direction I can move where the objective obviously grows without bounds towards +/- inf?
Finally, I also see questions where someone wants the tool to produce all possible solutions.
A truly good exposition about linear programming would probably result in a complete course on the subject, and Aswers is limited in how much I can write (plus I'll only have a finite amount of energy to keep writing.) I'll try to answer each sub-question as separate answers, but if someone else would like to offer their own take, feel free to do so as an answer, since it has been many years for me since I learned linear programming.
The 2022 community contests have concluded! During the 4 weeks, we hope you had a lot of fun and learned some MATLAB skills. Together, we've achieved amazing milestones:
- 500+ entries and 5,000+ votes created in the Mini Hack 2022 contest.
- 100,000+ solutions submitted in Cody 10th Anniversary contest
- 2,000+ participants in both contests

Now, it's time to announce weekly winners and grand prize winners!
Mini Hack - Pick of the MATLAB Graphics Team
We invited the MATLAB Graphics team, the authors of the MATLAB functions used in every entry, to be our Mini Hack judges. Here are their picks in 3 categories:
- Our Top 3:
Rising Hand by Augusto Mazzei
Object used: fill; Judge comments: Clever code, nice metaphor, kind comments
Above the clouds by Tim
Object used: patch (via VOXview); Judge comments: Very pretty, looks like it could be in a video game
Monocular rivalry by Jenny Bosten
Object used: Image; Judge comments: We spent a too much time trying to figure out what this illusion was doing to our brains
- Clever use of Charts:
Object used: Bar3; Judge comments: Cute! Nice fireworks!
Object used: histogram2; Judge comments: We didn't realize there was a ship in the flow data set
Object used: plot; Judge comments: Nifty and very different from other entries.
Object used: scatter; Judge comments: Overlapping markers make for a very cool tunnel-like effect
- Things we still loved:
Object used: image; Judge comments: Domain Warping FTW
Object used: surface; Judge comments: Clever use of transparency
Congratulations and you should be very proud of yourself! It's a huge achievement that your entry is recognized by the MATLAB Graphics team!
Mini Hack - special category for Week 4
Mini Hack - grand prize winners
After an intensive (and very time-consuming) review of votes on winning entries, we have finalized the list of grand prize winners. Huge congratulations! We appreciate the time and effort you spent and the awesome entries you created. Each of you won an Amazon gift card.
Anton Kogios, Brandon Caasenbrood, KARUPPASAMYPANDIYAN M, Teodo, Jenny Bosten, MvLevi, Abdullah Caliskan, Stewart Thomas, Jonas Schlatter, and Tim Davis
Cody 10th Anniversary - surprise prize for 28-day streak winners
We are thrilled to see that 37 players have built a streak of 28 days! Coming back every day to solve problems is an incredible achievement. We decided to show our appreciation by awarding a surprise prize to those 37 players. Congratulations! Each of you will get a MathWorks T-shirt.
Christian Schröder, Stefan Abendroth, Mohammed, Victoria, Vasileios Pasialis, Gerardo Domínguez Ramírez, HH, Anton Kogios, Lizhi Zhu, Marco Fuscà, Armando Longobardi, Monica, Rithik KRT, Ayman, Teodo, Lincoln Poon, Elijah Keifert, siranjeevi gurumani, kazuyoshi kouno, Ryan Koh, Manuela Kaiser, Mehmet OZC, Dyuman Joshi, KOTHAPALLI SRI BRINDA, Gergely Patay, abyss, Takumi, Keita Abe, Petr Cerny, Shubham Shubham, Meredith, Andrew K, Atsushi Ueno, Peter Orthmann, Armando Longobardi, Chuang Tao, and David Romero
Cody 10th Anniversary winners – Week 4
The top 3 players for solving the most problems in week 4 are Christian Schröder, Gerardo Dominguez Ramirez, and Stefan Abendroth, Congratulations! Each of you won an Amazon gift card.
Week 4 lucky winners are Qingrui Liu and Basant Ale.
Cody 10th Anniversary winners – grand prize winners
We know how hard it is to be a top-10 leader in the contest leaderboard! It requires a huge time commitment and advanced MATLAB skills. Congratulations! Each of you will win an Amazon gift card.
Christian Schröder, Stefan Abendroth, Mohammed, Victoria, Vasileios Pasialis, Gerardo Domínguez Ramírez, HH, Anton Kogios, Lizhi Zhu, and Marco Fuscà
Lucky voters and participants
Thank you for your participation in our 2022 contests. You don’t need to be on the top of the leaderboards to win. As we announced, we would give out 20 MathWorks T-shirts to lucky voters and participants of the 2 contests.
Ismail Bera Altan, Robin Stolz, Michael Mellin, Kellan Smith, Neha Shaah, Siranjeevi gurumani, Paul Villain, Andrew Horchler, Meg Noah, Saurabh Chaudhary, Pakize erdogmus, Godfrey Ojerheghan, Selena Mastrodonato, Damir Rasic, Thomas Kjeldsen, Meredith, John Noah Ramiterre, Patience Oliveira, Panda, and Sujeet Kumar Choudhary
On behalf of the MATLAB Central community team, we thank you for joining our celebration of the MATLAB Central community 2022 contests. We hope you enjoyed these contests and look forward to seeing you in next year’s contests.
How can I export data other than downloading it as a CSV file?
I want to embed the graphs in a website, how can I do that?
OR
How can I export data and display it on my own in the website?
You provided 10,958 anwers at the acceptance rate of 78.95% and received 3,126 votes. Thank you for your contribution to the community!
MATLAB Central Team
Hello everyone! does anyone know how to use the simulink write block for mobile android? I am attaching a cell phone error message. Thank you!
Hello
I am Jos
i have made a program for upload data to mine channels in pytython 2.7, now I am forced to go to 3.9 and I cannot get the program running
code for 2.7
import httplib
import urllib
def WriteData():
while True:
params = urllib.urlencode({'key': 'xxxxxxxxxxxxxxxx', 'field1': '0.021'})
headers = {"Content-typZZe": "application/x-www-form-urlencoded","Accept": "text/plain"}
conn = httplib.HTTPConnection("api.thingspeak.com:80")
try:
conn.request("POST", "/update", params, headers)
response = conn.getresponse()
print (response.status, response.reason)
data = response.read()
conn.close()
except:
print ("connection failed")
break
can someone help me with this code?
Hello,
I am trying to do image to image regression neural network training. In place of digitTrain4DArrayData, I have used my own dataset of 500 input and 500 output grayscale images of size 100*100 pixels for training.
The code is as follows:
imds1 = datastore(fullfile(matlabdrive,"T10itTI"),"IncludeSubFolders",true,...
"FileExtensions",".png","type","image");
imds2 = datastore(fullfile(matlabdrive,"TFiSTI"),"IncludeSubFolders",true,...
"FileExtensions",".png","type","image");
dsnew = combine(imds1,imds2);
layers = [
imageInputLayer([100 100 1])
batchNormalizationLayer
reluLayer('Name','relu_1')
convolution2dLayer(3,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_2')
convolution2dLayer(3,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_3')
convolution2dLayer(3,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_4')
convolution2dLayer(1,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_5')
convolution2dLayer(3,1,'Stride',2)
batchNormalizationLayer
reluLayer('Name','relu_6')
convolution2dLayer(3,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_7')
convolution2dLayer(3,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_8')
convolution2dLayer(3,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_9')
convolution2dLayer(3,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_10')
convolution2dLayer(3,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_11')
convolution2dLayer(3,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_12')
convolution2dLayer(1,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_13')
transposedConv2dLayer(1,1,'Stride',2)
batchNormalizationLayer
reluLayer('Name','relu_14')
convolution2dLayer(1,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_15')
convolution2dLayer(1,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_16')
convolution2dLayer(3,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_17')
convolution2dLayer(1,1,'Stride',1)
batchNormalizationLayer
reluLayer('Name','relu_18')
transposedConv2dLayer(3,1,'Stride',2)
fullyConnectedLayer(1)
regressionLayer
]
lgraph = layerGraph(layers);
options = trainingOptions("adam", ...
InitialLearnRate=8e-3, ...
SquaredGradientDecayFactor=0.99, ...
MaxEpochs=20, ...
MiniBatchSize=64, ...
Plots="training-progress")
net=trainNetwork(dsnew, lgraph, options);
On running the code, I get following error:
Error using trainNetwork Invalid training data. The output size ([1 1 1]) of the last layer does not match the response size ([1 1 1972224]).
When I use fullyConnectedLayer(1972224) in place of fullyConnectedLayer(1), I get following error:
Error using trainNetwork Layer 'fc': Invalid initializer. Requested 1972224x17161 (252.2GB) array exceeds maximum array size preference (5.0GB). This might cause MATLAB to become unresponsive.
Error in mt1tt1 (line 95) net=trainNetwork(dsnew, lgraph, options);
Caused by: Error using nnet.internal.cnn.assembler.InitializeMixin/initializeLearnableParameters Layer 'fc': Invalid initializer. Requested 1972224x17161 (252.2GB) array exceeds maximum array size preference (5.0GB). This might cause MATLAB to become unresponsive.
Can you suggest correction in code?
Thankyou
Dear Community,
I'm new on ThingSpeak for nearly 4 weeks and I'm struggling to compute some MATLAB data. Mostly because I don't know the syntax.
I have a hourly graph of solar production in kW, I'm taking a sample every 20 seconds, and I would like to aggregate the data on a daily basis in kWh.
I guess I need to select the last 7 days of data using some thingsread function, add the data into an array and compute the daily data into an average/sum ... As you can see, I mostly got the mechanics but I'm struggling to create the car ;) Is there anyone kind enough to assist me ?
Thansk a lot !
Hallo, ich bin Anfänger und beschäftige mich gerade mit dem ELV-Modulsystem mit dem man über Steckmodule eine Sensor-Datenstation aufbauen kann, die Temp und Hum misst . Die Daten gehen dann vom Modul zu TTN und werden dort dann in einer decodierten Payload ausgegeben. Mittels Webhook Integration zu ThingSpeak will ich die Daten dann in zwei Felder-Widget für Temp und Hum ausgeben/auswerten.
Der erste Teil funktioniert und die Payload wird ausgegeben. Die Daten darin sind vernünftig.
Nun habe ich in TTN eine Integration mit Webhook "ThingSpeak" erstellt und den Decoder um zwei Zeilen entsprechend erweitert in denen Die Temperatur-Variable in "field1"-Variable geschrieben wird und die Humidity in eine "field2"-Variable.
Leider wird aber nicht wie erwartet die Datenausgabe in ThingSpeak erledigt. Die Field-Widgets bleiben leer.
Kann mir jemand helfen? Was mache ich falsch?
Hello, I'm a beginner and I'm currently working with the ELV module system with which you can set up a sensor data station using plug-in modules that measures temp and hum. The data then goes from the module to TTN, where it is then output in a decoded payload. Using webhook integration with ThingSpeak, I then want to output/evaluate the data in two field widgets for Temp and Hum.
The first part works and the payload is output. The data in it is reasonable.
Now I have created an integration with the "ThingSpeak" webhook in TTN and extended the decoder by two lines in which the temperature variable is written in a "field1" variable and the humidity in a "field2" variable.
Unfortunately, the data output in ThingSpeak is not done as expected. The field widgets remain empty.
Can someone help me? What am I doing wrong? Thanks
In Week 3, several new milestones have been achieved! Cody 10th contest has reached the 80,000-solution milestone! Mini Hack has over 400 entries. @Tim Davis’ seashell entry actually inspired a MathWorks blog post. Check it out.
During the last week of this contest, we strongly encourage you to inspire your colleagues, classmates, or friends to vote. Let the world know the beauty of Mathematics. Voters will also have the opportunity to win a MATLAB T-shirt.
MATLAB Mini Hack Winners - Week 3
In week 2, we announced the special category for week 3 is nature. Below are the 3 winners for this category.
- Tim , entry: Orchid,
- Shanshan Wang , entry: Colorful butterfly
- Tim Davis, entry: seashell
Winners of other categories are:
- Jenny Bosten, entry: Galaxy, category: space
- Paul Villain, entry: modfun spiral, category: colorful
- Brandon Caasenbrood, entry: Beauty of Discrete-Time Attractors, category: black & white
- Anton Kogios, entry: Parallel Lines?, category: illusion
Congratulations! Each of you won a T-shirt. I just heard we have 4 designs of MATLAB T-shirts. Can you collect all of them?
Cody 10th Anniversary Winners - Week 3
- The top 3 players for solving the most problems in week 3 are Christian Schröder, Marco Fuscà, and Stefan Abendroth, Congratulations! Each of you won an Amazon gift card.
- As long as you participate, you have the opportunity to win MathWorks T-shirts. Week 3 lucky winners are Luffy Wangand Augusto Mazzei.
What’s new in week 4?
MATLAB Mini Hack 2022:
- Week 4’s new category is holiday! Halloween is around the corner. What holidays are you celebrating?
- You are able to leverage Signal Processing Toolbox in your entry.
Cody 10th Anniversary:
- Are you smart than a MathWorker? Challenge yourself by solving our Week 4 special problem group: Are You Smarter Than a MathWorker?
I am using the datastreamer addin in MS Excel for collecting sensor data. No I would like to write the data one by one to a thinkspeak channel. I need a VBA code example to learn more about this.
Thank you very much.
Hallo,
ich habe an meinem Raspi den DHT22 angeschlossen und die Werte werden mir auch korrekt ausgegeben,
jedoch wird mir bei Thingspeak keine Charts angezeigt, obwohl ich Read/Write API sowie Channel im Skript angegeben habe.
Nach folgender Referenz bin ich vorgegangen:
Hat noch jemand dieses Problem?
Want a MATLAB T-shirt? We have 10 more to give out in the 10 days between now and Oct. 30th. You might win a MATLAB T-shirt by doing any of these activities:
- Vote on entries you like from the Mini Hack contest
- Solve Cody problems in the Cody 10th contest
- Create or remix entries in the Mini Hack contest
The more activities you do, the higher your chance to win. Every day, we will pick a winner.
What amazing images can be created with no more than 280 characters of MATLAB code? Check out the GALLERY from the MATLAB Mini Hack 2022 contest.
Vote on your favorite MATLAB images before Oct. 30th! We will give out MathWorks T-shirt to 10 lucky voters.

How can I vote?
You can vote for an entry by clicking on the heart icon on an entry card or the vote button on the entry detail page.

Hi every one. I am new to thingspeak. I want to share data between my siemens PLC and thingspeak channel without any use of PC. Cna anyone help me out with the ways of communication and harware needed for the application.
Note: I have created channel in thingspeak website. I need support for siemens PLC programming for data sharing.
Pls guide me.
Hi there!
There is a question, is it possible to send plot data from my channel to telegram bot as image file using ThingSpeak API or some other tools?
We had another wonderful week of community contests 2022. In week 2, the voting for Mini Hack started! About 1000 votes have been cast on 300+ entries. In Cody 10th Anniversary contest, we already have 85 finishers for the two special groups: Matrices and Arrays and Plotting and Visualization.
Now, it’s time to announce the weekly winners!
MATLAB Mini Hack Winners - Week 2
Amazing entries keep coming in every day. In week 2, we announced a space category to celebrate the milestone of NASA’s Dart mission. We’ve picked 4 winners for this new category.
- Stewart Thomas, Lunar Shadows, category: space
- Teodo, NASA's DART Dimorphos Impact, category: space
- Simon Thor, Starry night, category: space
- Abdullah Caliskan, spacetime, category: space
Winners of other categories are:
- MvLevi, Personlized Lyapunov Fractal, category: File Exchange
- KARUPPASAMYPANDIYAN M, Moon View at MATropolis!, category: File Exchange
- Jan Studnicka, Butterfly, category: animal
- Brandon Caasenbrood, Periodic Minimal Surface, category: 3d
- Basil Imoberdorf, Zoom of Fractal action #3, category: fractals
- Pink_panther, Seaweed on Pandora, category: nature
Congratulations! Each of you won a MathWorks T-shirt. If this is the second time you won, you have the option to choose a MathWorks hat or a coffee mug!

Cody 10th Anniversary Winners - Week 2
- The top 3 players for solving most problems in week 2 are Mohammed, Armando Longobardi, and Stefan Abendroth, Congratulations! Each of you won an Amazon gift card.
- You don’t need to be an expert or spend tons of time to win! As long as you participate, you have the opportunity to win MathWorks T-shirts. Week 2 lucky winners are Dylan Baker and Takumi.
What’s new in week 3?
MATLAB Mini Hack 2022:
- Week 3’s new category is nature! We look forward to seeing more nature-themed creative entries from you!
- You are able to leverage up to 2 File Exchange submissions in your code.
Cody 10th Anniversary:
- Week 3 special problem group is Programming Constructs. Have fun!