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Currently, I am on a test account with Thingspeak but it would be no problem to upgrade to a subscription plan if it provides the required features.
I would like to edit the time scale (currently only around 10h) and export time (currently only around 24h) for the graphs and the export function in the public channel.
How is this possible? It would be nice to have the option to plot 12h, 1d, 1w, 1m etc. in the graphs and also have the respective export function.
AI, Robotics, Autonomous Systems: MATLAB EXPO is coming up soon and it is time to register. It's free and open to everyone. You will have the opportunity to connect with engineers, scientists, educators, and researchers, and new ideas.
disp('It is time to register for MATLAB EXPO 2023!');
Featured Sessions:
- Project-Based Learning and Design with Simulation - Professor Claire Lucas, King’s College London
- How Siemens Energy Enables the Global Energy Transition - Jens Dietrich, Siemens Energy AG
Features Topics:
- AI
- Autonomous Systems
- Electrification
- Robotics
I have purchased an 8in1 weather station from Seed (see Link here), added it to TheThingsStack v3 and changed the payload formatter such that I receive following payload:
{
"barometric_pressure": 96920,
"battery": 0,
"humidity": 92,
"light_intensity": 11848,
"rain_gauge": 0,
"temperature": 6.8,
"uv_index": 0.6,
"wind_direction": 60,
"wind_speed": 0
}
I have followed the ThingSpeak manual here, which seems pretty straight forward to me: just add channel ID and Write Api Key.
However, on TheThingsStack, I see following error:
"data": {
"@type": "type.googleapis.com/ttn.lorawan.v3.ErrorDetails",
"namespace": "pkg/applicationserver/io/web",
"name": "request",
"message_format": "request",
"correlation_id": "XXXXprivate",
"code": 14,
"details": [
{
"@type": "type.googleapis.com/google.protobuf.Struct",
"value": {
"body": "error_too_many_requests",
"status_code": 429,
"url": "https://api.thingspeak.com/things_network/v3/update/",
"webhook_id": "loraweatherstation"
}
}
]
},
[...]
"visibility": {
"rights": [
"RIGHT_APPLICATION_TRAFFIC_READ"
]
TheThingSpeak reports entries without the actual data. I think the entries are generated with all get requests.
Congratulations, @John D'Errico for winning the Editor's Pick badge awarded for MATLAB Answers, in recognition of your awesome solution in How to fit a biexponential decay function
You explained the general process of solving this problem and explored several options until he got to the a good model. This is very instructional and would be useful for anyone who run into similar problems.
Unfortunately, you can only get this badge once - so there will be no new badge for you this time, but we nonetheles appreciate your ongoing effort to help other users in the community. Thnk you so much!
MATLAB Central Team
Hello,
can someone help me with HEV model? I have no experience with simulink modeling, maybe someone have any simple HEV models or any tutorials how to start everything? :)
Thank you.
Dear team,
i have issue regarding not shown values thingspeak
I am using simulink to generate a simple ADC sampling code. I configured ADC module in software mode, which updates the sampled value according to the sample time configured in the module. I set the sample time to 1e-4, 1e-5, 1e-6 respectively. But it seems that the sampling speed did not reach the value I set. I suspect it has something to do with the read and write operations, but I am not sure if that's the reason.
I also tried to do it using PWM event to trigger the start of conversion of ADC. Same problem happened. Because I connect a potentiometer and turn its knob slowly, the Graph on CCS is correct while when I turn it very quickly, the graph is not able to keep up with my movements. So the sampling rate is surely not enough. I wonder what I should do to successfully configure this model, thanks in advance!
Bonjour,
pour un projet d'école j'ai besoin de faire analyser des données saisies directement dans Appinventor et non pas à partir de capteurs. J'ai cherché un peu partout sur le web mais je n'ai pas trouvé la solution. Quelqu'un peut il m'aider ?
Hi there,
Truncation error happens when an infinite series is ignored except for a small subset of its values. For instance, the exponential function e^x could be written as the infinite series total of 1 + x + x^2/2 + x^3/6 +... + x^n/n! +....
Any finite number of n will result in an approximation of the value of e^x that is inaccurate, but by increasing n, the error can be reduced to the desired level but this increase computation time.
How can I speed up the calculation by determining the dynamic level where error can be reduced to the barest minimum?
The error is different for each input; if the input number is small, the error condition can be reached quickly, say 1e-6; if the input number is large, we need more terms in the polynomial equation, i.e. more iteration; how can I make the threshold dynamic so that I don't have a fixed error tolerance number?
What I want to know is how to make the threshold dynamic so that I can decrease the polynomial's order and lower the number of terms, which will speed up execution time.
Any assistance would be greatly appreciated.
format long e
[exp(log(2)/2), 1+log(2)/2 + (log(2)/2)^2/factorial(2) + (log(2)/2)^3/factorial(3) + (log(2)/2)^4/factorial(4),(exp(log(2)/2) - 1+log(2)/2 + (log(2)/2)^2/factorial(2) + (log(2)/2)^3/factorial(3) + (log(2)/2)^4/factorial(4))]
[exp(-log(2)/2), 1+(-log(2)/2) + (-log(2)/2)^2/factorial(2) + (-log(2)/2)^3/factorial(3) + (-log(2)/2)^4/factorial(4),(exp(log(2)/2) - 1+log(2)/2 + (log(2)/2)^2/factorial(2) + (log(2)/2)^3/factorial(3) + (log(2)/2)^4/factorial(4))]
Hello,
I have an Open Loop Transfer Function:
Gc(s)Gp(s) = aKp(1+Tis) / Tis(s+1+p)
It was decided for this system a=5, Ti=0.1 and p=0.5
What would the poles and zeroes be for this?
Ive done the other examples but this one looks very different to the other questions and it has me stuck.
Any help is appreciated and sorry if this is the wrong place to post such questions.
"The model is configured to create a SIL block, which is not supported for the selected hardware board. To resolve this, search for 'Create block' in the Configuration Parameters dialog box and set it to 'None' or 'PIL'.
I am using the standard code written by Daniel. The temperature is giving -11.8 and the humidity 150. This is not for all data points. Any help would be appreciated
If you use MATLAB online, you might already know about the advanced search feature that groups your results into the top suggestions by type of result – such as examples functions or blocks. This release, there is a new group for video results: you can see an icon sized thumbnail and the video length all in the search box dialog.
Try out all the search groups - you can even try it out in dark mode!
Heather and Yann talk about their journeys that span both open-source and MATLAB and Jousef ask them what they think of MATLAB vs. Python, and AI in general, including ChatGPT. It is a very casual and open conversation about range of interesting topics. Don't miss it!
hi,
I have a web page which i need to enter user and pass in pop up combo box when i enter the site.
also i can enter directly with http://user:pass@x.x.x.x:port this format witour entering user and pass in combo.
i can not manage to get data from thingHttp and mathlab analysis. I always get http 401 error.
How can i can data? is it pıssible with thinkSpeak?
Hello,
I got the following error when I was trying to run the codes below. I'm glad if someone can tell me the reason for getting this error.
Thank you!
Error:
Unable to perform assignment because the size of the left side is 1-by-1 and the size of the right side is
1-by-201.
Error in fminsearch (line 201)
fv(:,1) = funfcn(x,varargin{:});
Error in fminsearchtest (line 47)
[fitparams_out, fval, ~, ~] = fminsearch(fn, fitparams_guess, options);
Code:
options = optimset('Display', 'iter', ...
'TolX', 1e-6, ... %Termination tolerance on x, default is 1e-4
'TolFun', 1e-6, ... %Term. tolerance on function value, default 1e-4
'MaxFunEvals', 1000 );
fitparams_guess=[0 0 0];
Noise = 2;
C0=pi;
C1 = 2;
C2 = 0.8;
x = -10:0.1:10;
y = C0 + C1*x + C2 * x.^2 + Noise*randn(1,length(x));
fn = @(fitparams) calc_residual(fitparams, x,y); %function handle
[fitparams_out, fval, ~, ~] = fminsearch(fn, fitparams_guess, options);
function residual = calc_residual (fitparams, x,y)
for i =1:length(x)
ymod = fitparams(1) + fitparams(2)*x(i) + fitparams(3) * x(i).^2 ;
end
residual = y-ymod;
end
Hello,
I am setting up a home energy monitoring system, all started from a blank sheet in arduino and its really working very well.
I would like to send data to thinkspeak which is not time dependant, i.e. send the X and Y values and format as a bar graph. The reason is, i have 12 channels monitoring energy (Wh) and i have this in an array which i plot on a local LCD and throughout the day the bars grow in height as the usage attributed to that channel grows. How can i do something similar in thing speak which by default applies a time stamp to received data.
Very simply, each channel has an ID (0-11) and a number associated with the accumulative Wh. I have a similar thing in excel for development where my serial port data is saved to a csv which excell imports every minute and updates a bar graph a bit like this;
Ive had a good look (perhaps not good enough!) and i just cant see how this may be acheived with thingspeak without a clumbersome combination of 2 channels (given each channel has 8 fields) and then using a matlab visualisation to pull it all together. Perhaps its not has hard / messy as it sounds? I am paid user so can create extra channels if required.
Thanks,
Stuart
