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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
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)
Sanika Patil
Sanika Patil
Last activity on 25 Nov 2023 at 4:39

face recognition GUI

Error using matlab.ui.control.internal.controller.ComponentController/executeUserCallback Error while evaluating Button PrivateButtonPushedFcn.
help to solve this error in face recognition GUI
丰 年
丰 年
Last activity on 23 Nov 2023 at 9:25

打开matlab 示例 提示错误

打开matlab 示例 提示错误,提示“系统找不到指定的文件”
Shaunak Deshpande
Shaunak Deshpande
Last activity on 20 Nov 2023 at 20:21

Error using tall/cellfun

I'm getting an error error "using tall/cellfun" while doing a project listed in mathworks "Denoise Speech Using Deep Learning Networks". I don't know how to fix this error pr why this error occured in the first place. Seeking explanation for this particuar error. If you know anuthing about it then please consider helping me below this post.
Project link
柯
柯
Last activity about 15 hours ago

Two-phase flow solenoid valve

Hello, I want to use a solenoid valve to open and close the two-phase flow circuit, and I should use those elements to achieve it.
Adrian Segura
Adrian Segura
Last activity about 1 hour ago

neural networks

Hello, I am a student and I am working on a neural network for a line follower car and I would like you to recommend a tutorial to implement it in simulink.
Raja
Raja
Last activity on 14 Nov 2023 at 18:32

Undefined variable "handles" or class "handles.ik5".

Hello everyone! I'm new in MatLAB and i get confusing because i cannot run my program.
set(handles.ik5,'string',ik5);
set(handles.es5,'string',es5);
set(handles.el5,'string',el5);
-------------------------------------------------
Undefined variable "handles" or class "handles.ik5".
Error in Untitled (line 4)
set(handles.ik5,'string',ik5);
Hi, I'm in truble because I have two programs with the same variables and parameters. The main of the study is to change a value and plot the results. The problem is that I want them on the same plot but I use the same name for the variabes in the two different programs so when I use some function to join the figures togheter matlab resets the values obtained in the first program and runs only the second one.
Is there a method to avoid changing all the names of the variables in one of the two programs (because they have something like 500 lines)?
Hi everyone,
I would like to ask you if it would be possible to do an HiL simulation using an environment model simulated via Simulink and load in a target computer connected to the hardware needed. The target computer will be simply a laptop with Matlab&Simulink package installed and directly connected to the bench to test.
I have found some solutions about the use of Simulink Real-Time but it implies the use of a Speedgoat unit, so I was wondering if anyone has ever done it without that device.
Thank you very much.
Hello,
I have an equation model following a law of type power: s=aN^b
For the measure equation, I have also a power law: m=cN^d
So I would like to have an extended Kalman Filter code in Matlab for this case. CAN YOU HELP ME PLEASE ?
Hello.
I use readgeoraster to read in a 25MB geotiff. I then turn around and immediately write out the data with geotiffwrite. The resultant file is now 250MB.
What is the explanation for this 10x increase in file size? The data read in are 'single' format. And that is the exact data I am writing out.
Dave
Christine
Christine
Last activity on 8 Nov 2023 at 1:04

Need help with my assignment

i need to create an app in app designer that is able to convert ac to dc. i already created the layout of the app and i created a curcuit that is able to convert ac to dc in sumilink. but i am having troubles linking the circuit simulation to the app.
Basically, i want the user to input the voltage in the app and it should send that data to the simulation and the output should come back to the app.
仟仟
仟仟
Last activity on 9 Nov 2023 at 6:17

Parameter output problem of genetic algorithm

When I apply genetic algorithm to find the optimal parameter, before the parameter enters the algorithm, I have controlled the parameter to keep two decimals in their respective ranges, but when the final output, the optimal parameter returned is really six decimals. Why? What am I supposed to do? (Note: I need to keep two decimal places in the parameter before entering the algorithm, because a change of 0.001 in the parameter has a great effect on the result, so I can't round the result directly.)Look forward to your reply~
LAWAN HARUNA
LAWAN HARUNA
Last activity on 6 Nov 2023 at 19:08

mentorship

good afternoon everyone my name is Dundu lawan haruna ,i'm a final year student at the department of computer engineering ABU Zaria, Nigerian , and i wanted to do my final year project based on computer vision : project topic , designing an eye glasses to help those people with visual imparement to be able to navigate enviroment efficiently , that's why i need a support from you guys ,all advised are highly well come , thank you for your support.
Willis
Willis
Last activity on 5 Nov 2023 at 15:59

motor control using PLL

Can anyone kindly assist me in this topic

Good day community, can I know what is this symbol could be? It looks like a ramp/ continuous ramp. But I believe it is not both them. I saw someone connect it after a voltage/ current measurement. Can I know what is the function of this symbol too? Much appreciate for the answers given

Hello All,
I was wondering, from which version Tracebility Diagrams are available (in SLK Req)?
Regards
Abhishek KUMAR
Recently, I came across a post about the JIT compiler on this Korean blog. In the post. The writer discussed the concept of the "Compile Threshold" and how it is calculated.
"The JVM accumulates the number of calls for each method called and compiles when the number exceeds a certain number. In other words, there is a standard for checking how often it is called and then deciding, 'It is time to compile.' This standard is called the compilation threshold. But what is this and why should it be used as a standard?"
The concept of the "Compile Threshold," as used above, seems to be more commonly associated with Tracing just-in-time compilation.
The writer used the simple Java code below to calculate the threshold.
for (int i = 0; i < 500; ++i) {
long startTime = System.nanoTime();
for (int j = 0; j < 1000; ++j) {
new Object();
}
long endTime = System.nanoTime();
System.out.printf("%d\t%d\n", i, endTime - startTime);
}
Since the MATLAB execution engine uses JIT compilation, I just wanted to perform the same experiment that the writer did.
I experimented using simple codes based on the code in the blog. I iterated a function 500 time using for-loop and calculated the execution time for each iteration using tic and toc. Then I plotted the execution time for each loop as blow. First five execution times are much higher than followings (10 times!) The test is very rough so I am not sure that I can conclude "MATLAB has Compile Threshold and it is 5!" but this value is actually correct ;-)
t0 = 0;
tfinal = 10;
y0 = [20;20];
timeToRun = zeros(500,1);
for i = 1:500
tStart = tic;
[preypeaks,predatorpeaks] = solvelotka(t0, tfinal, y0);
tEnd = toc(tStart);
timeToRun(i) = tEnd;
end