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Atakan
Atakan
最後のアクティビティ: 2023 年 12 月 1 日

Hello everyone. I'm beginner at MATLAB and I have 12 lead ECG database for my project. I have to see and investigate ECG signal but I couldn't find how to do it. Does anyone know how to combine these 12 lead data and obtain a clear ECG?
Zdenek
Zdenek
最後のアクティビティ: 2023 年 12 月 1 日

Hi,
I am now to appbulding, however I'am trying to build a app with appdesigner, but I cant find out how to change baground color of tree subnode and how to change color of text in subnode.
Is it even possible in appdesigner or in Matlab?
Or can I somehow use html to do this?
Can you help me find the solution?
Thank you very much.
Siebe Caems
Siebe Caems
最後のアクティビティ: 2024 年 2 月 7 日

Hello,
What is the difference between a moving angle and a normal angle?
Compute the Rotation about Y-axis over moving angle a = 30°
then
rotation about X-axis of angle β= 45°
What will the code like?
Thank you
Have you marveled at the breathtaking, natural-looking animations crafted by the creative minds in the Flipbook Mini Hack contest? Think of @Tim, @Jenny Bosten, and @Zhaoxu Liu / slandarer- their work is nothing short of extraordinary.
So, what's their secret? Adam Danz, a developer in the MATLAB Graphics and Charting team and a top community contributor, has graciously unveiled the mysteries in his latest blog post - "Creating natural textures with power-law noise: clouds, terrains, and more." The post offers simple, step-by-step instructions and code snippets, empowering you to grasp these enchanting techniques effortlessly.
Check it out and we hope it sparks your creativity and serves as a wellspring of inspiration. With only 3 days remaining before the contest draws to a close, it's time to dive into the code and let your imagination soar!
Meriem zanoun
Meriem zanoun
最後のアクティビティ: 2023 年 12 月 1 日

Hello everyone, I'm using Simulink for running simulations, and I'd like to call a trained machine learning model (in my case, a TreeBagger) in MATLAB to make predictions in Simulink. However, I'm having some trouble with it. Has anyone already worked with this?
Engineer
Engineer
最後のアクティビティ: 2023 年 12 月 11 日

Hello there, I have a Amesim Black box model in Simulink. On my desktop, it works well. Also i tried to run on other desktops. Most of them work well. But some of them gives following error: Error in 'Model' while executing C MEX S-function 'Model', (mdlInitializeConditions), at time 0.0. Caused by: in Simcenter Amesim mexfunction: 'Model', Simcenter Amesim fatal error Cannot initialize Simcenter Amesim Model. EXIT This is an urgent case for me. Could you please help me?

Thank you so much.

Kali
Kali
最後のアクティビティ: 2023 年 12 月 21 日

Write a matlab script that will print the odd numbers, 1 through 20, in reverse.
I cannot figure out how to do this correctly, please help.
Dear Community,
I am trying to perform PowerGUI Loadflow analysis for EV Charging station. The model converges but the load flow vaues on the DC bus is zero. Whether power_loadflow supports Mixed AC/DC load Flow.
Can someone help me by providing guidance on how to preform the same
Regards
Vara
when I build the model I get the name mismatch error for two calibratable signals . The signals are in the data dictionary , and I use them in the model by pulling from the dd with the same name . can anyone point me out what possibly cause this error?
Marcin Kowalski
Marcin Kowalski
最後のアクティビティ: 2023 年 11 月 28 日

Hi all,
The question is simple as the title says. How to consume messages from selected Kafka topic?
I have a setup which works perfectly from terminal and now I am trying to connect MATLAB with this Kafka topic, just to consume messages. I followed this:
but unfortunately there is no information how to consume messages. Any help will be appreciated!
K Kalanithi
K Kalanithi
最後のアクティビティ: 2023 年 11 月 28 日

How to write a script for single mpc controller to multiple sysytems? then plot the response in same graph and differentiate the system dynamics.The above figure for PID likewise for MPC anf commands or codes?
Bar
Bar
最後のアクティビティ: 2023 年 11 月 28 日

I'm plotting an error with respect to the number of points used.
Now there are three different ways to comput the error, and I always plot the maximal error.
If the maximum is for computation 1, I want the dot in the plot to be red, for computation 2 it should be blue, etc.
How can I achieve this? My data is in a n x 2 matrix
Chen Lin
Chen Lin
最後のアクティビティ: 2023 年 12 月 4 日

In Week 3, we reached the 400-animations milestone! Let’s work together to achieve the 500-animations goal!
During the last week of the contest, we strongly encourage you to inspire your colleagues, classmates, or friends to vote. Voters will also have the opportunity to win a MATLAB T-shirt.
Mini Hack Winners - Week 3
Math, Physics, or Science explanation:
Most creative remix:
40:
Math is beautiful:
Mashup (Combined themes):
Jr / balloons IV (40 & multi-entry story)
Nature:
Holidays:
Congratulations, winners!
In week 4, we’d love to see more entries in the following categories:
  • Holidays:
  • Seasons:
  • Abstract:
  • Mashup (mixed categories)
A gentle reminder that you have a direct impact on the next generation of animation tools in MATLAB! Don’t forget to share your thoughts and ideas with us.
Bewar Yousif Ali
Bewar Yousif Ali
最後のアクティビティ: 2024 年 2 月 7 日

It is crucial to understand that this expression could be used in problems related to engineering, physics, mathematics, or any other aspect of real life.
Typically, Matlab is used to solve PDE and ODE problems. Perhaps users calculated this term 0^0 incorrectly in the process.
>> % Reviewed by Bewar Yousif Ali
>> % How to fix this problem 0^0 in Matlab !?
>> % Mathematically, x^0=1 if x≠0 is equal 1 else undefined(NaN)
>> 0^0
ans =
1
>> f=@(x,y) x^y;
>> f(0,0)
ans =
1
>> v=[2 0 5 -1];
>> v.^0
ans =
1 1 1 1
i=dsolve('Dy=-8*y+40*sin(8*t)','y(0)=5')
Warning: Support for character vector or string inputs will be
removed in a future release. Instead, use syms to declare
variables and replace inputs such as dsolve('Dy = -3*y') with syms
y(t); dsolve(diff(y,t) == -3*y). > In dsolve (line 126)
Andrea Lanza
Andrea Lanza
最後のアクティビティ: 2023 年 11 月 27 日

Hi all, I have to train a one class SVM for anomaly detection. I have a dataset with two features. I trained the model on normal instances with ocsvm function. What I don't understand are the contour lines for the ocsvm scores... I do not expect those to be like that. In the figure are represented the normal instances in the space (feature1, feature2) and the contour lines corresponding to some values of ocsvm score. They are simply absurd, not like the example see on the matlab guide. I would expect ellipsoidal contour lines, not these! Any help? Thank you!
Perky Whale
Perky Whale
最後のアクティビティ: 2023 年 11 月 27 日

I have a few ESP8266 running various sensor tasks, and sending GET or POST requests to Thingspeak via api.thingspeak.com. They all connect to the household router.
Recently, I became aware of a problem with the devices occasionally timing out when trying to communicate with Thingspeak. For example, here's a bit of code from a basic water level sensor:
String url = "http://api.thingspeak.com/update?api_key=xxxxxxxxxxxxx&field1=";
url += getdistance();
url += "&field8=";
url += batt;
http.begin(client, url);
int httpcode = http.GET();
Serial.println(httpcode);
String payload = http.getString();
Serial.println(payload);
http.end();
Fairly often, the connection will fail with a -1 httpcode. Sometimes it will run for weeks with no issues and then suddenly stop connecting. If I type the URL in a browser, it will always work immediately. If I connect the ESP to a mobile hotspot, it will also connect immediately with no issues. I can't find any issues at all with the router, and I've fully reset it etc. I've also confirmed the wifi connection between ESP and router is not the problem.
Sometimes one ESP will be running fine, and another will be having connection issues. The next day, the first one will have issues and the other will be fine.
So I added a bit of code to see if I could time the connection:
server = "api.thingspeak.com"
timer= millis();
while(client.connect(server,80)){
delay(10)}
t=millis()-timer;
Serial.print(t);
The devices now connect every time. But the connection can take up to 180 seconds. Some ESP's updating to older channels are much more reliable and connect within a second or two; it seems as though the more recently created channels take longer to connect to.
I'm reaching out here because I can't really think of where to begin trying to fix this. Why does a browser succeed immediately updating a channel with the api.thingspeak url but the ESP takes up to 180 seconds? Why do I not have any problems connecting the ESP via a mobile hotspot? Why does the same device work for weeks then suddenly play up?
I think I've isolated the problem to either the router or the thingspeak api, and I can't find anything wrong with the router.
Might be worth noting that I have an ESP in a heat pump which updates every 15 seconds to thingspeak by MQTT and it hasn't skipped a beat in months so maybe I should upgrade them all to MQTT.
Is the api just that flakey?
JAMEEL
JAMEEL
最後のアクティビティ: 2024 年 2 月 6 日

% Given data
x = [2.0, 3.0, 6.5, 8.0, 12, 15];
f = [14, 20, 17, 16, 23, 125];
% Construct the cubic spline
h = diff(x);
A = zeros(length(x)-2);
for i = 1:length(x)-2
A(i,i) = 2*h(i) + 2*h(i+1);
A(i,i+1) = h(i+1);
A(i+1,i) = h(i);
A(i+1,i+1) = 2*h(i) + h(i+1);
end
b = [6*(f(2)-f(1))/h(1) + 6*(f(3)-f(2))/h(2);
6*(f(4)-f(3))/h(3) + 6*(f(5)-f(4))/h(4)];
M = A\b;
% Evaluate the second derivative at data points
d2f_dx2 = zeros(length(x),1);
for i = 1:length(x)-2
d2f_dx2(i) = M(i);
d2f_dx2(i+1) = M(i) + h(i)*M(i+1);
d2f_dx2(i+2) = M(i) + 2*h(i)*M(i+1) + h(i)*h(i)*M(i+2);
end
% Display second derivatives at data points
disp('Second Derivatives at Data Points:');
disp(d2f_dx2);
Sanika Patil
Sanika Patil
最後のアクティビティ: 2024 年 2 月 19 日

Error using matlab.ui.control.internal.controller.ComponentController/executeUserCallback Error while evaluating Button PrivateButtonPushedFcn.
help to solve this error in face recognition GUI
Shiwani
Shiwani
最後のアクティビティ: 2023 年 11 月 27 日

Hi I have a user defined blocks for my Simulink but whenever I add path of user defined, the error pops up stating I dont have stateflow.
Can anyone please guide me through it.