error in ode45 - function must return a column vector
It would help to have ‘dirfield’ (whatever it is). The other problem is that with one differential equation, ‘y0’ has to have o...

13 dagar ago | 0

How to convert displacment data in time series to frequency domain ie (from Amplitude (m) v/s time (s) to Amplitude (m) v/s Frequency (Hz)) using fourier transform
I wrote a utility function to do Fourier transforms. Try this — A1 = readmatrix('ellipse_r3.xlsx') figure plot(A1(:,1),...

15 dagar ago | 0

How to interpolate data as stairs
You answered your own question — stairs. Note that you can get the (x,y) coordinates as outputs from the stairs function if you...

15 dagar ago | 0

How to remove noise of low frequency signals
Calculate the fft of the green signal (if you do not already know its spectral qualities), then use it to define the cutoff freq...

16 dagar ago | 0

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How to detect the specific area from an oscilloscope signal
Perhaps something like this — jpgs = dir('*.jpg'); csvs = dir('*.csv'); for k = 1:numel(jpgs) figure imshow(imre...

16 dagar ago | 1

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Symbolic expression simplification and shortening
The expression is apparently incomplete. Working with what is provided — syms e e1 e2 h1 h2 h3 A B U = 108*A^2*e^7*e1^3*...

17 dagar ago | 0

How do I check if there is a function with the same name
The which function can be helpful. which which -all If there are any others in your MATLAB search path, it should display th...

17 dagar ago | 2

How to italicize a portion of a plot label while keeping the sans-serif font?
A lot of the LaTeX options do not work in MATLAB because many of the font options are not supported. That aside, use \it to b...

18 dagar ago | 0

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Peak coming at 50Hz in every data file. How to get rid of that
If you have the Signal Processing Toolbox, use the bandstop function: Fs = ...; ...

18 dagar ago | 0

how can I find the intersect point of 1 plot and a yline ?
Use interp1 for this — x = [0 10 20 30 40 50 60 70 80 90]; y = [0 0.0328 0.2521 0.7975 1.7295 3.0213 4.5714 6.2283 7.819...

19 dagar ago | 1

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OBTENTION OF AN ABSORBANCE SPECTRA FROM AN IMAGE
Without some sort of calibration, what you want to do might not be possible, especially if the resolution is only integers on th...

19 dagar ago | 0

Indexing of cell array and a vector
One approach — index = {[0], [0], [5], [0], [6, 7], [0], [0], [1], [0], [0], [0], [ 3]} ; data = [100, 10, 20, 15, 11, 25, 2...

19 dagar ago | 0

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how to choose windwo size in the EMG signal ?
I am not certain where you read it either, or the rationale for that particular window length calculation. I am not aware of ...

20 dagar ago | 0

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How can I read CDF file?
Without having the file to work with, writing specific code to work with it is not possible. Start with the cdfread function...

20 dagar ago | 0

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How to store users input in a file?
If you want to read the file, try something like this — % name = input('What is your name? ','s'); % age = input('How old are...

21 dagar ago | 0

How do I fit a 3rd order polynomial Basis using fitrgp?
From the documentation, using a table as input: Each row of Tbl corresponds to one observation, and each column corresponds to...

22 dagar ago | 0

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Displaying Text on Paper
Without knowing more about this, one option would be to use the axis function to extend the axis limits. Then the text function...

23 dagar ago | 0

How to use Matlab to generate a discrete uniformly distributed decimal with a value range of {0, 0.05} and a step size of 0.01?
Perhaps something like this — rv = randi([0 5], 1, 100)/100 figure histogram(rv, 5) grid .

23 dagar ago | 0

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User defined function for curve fitting, but the defined function is complicated
I thought it had something to do with scaling . That would depend on the magnitude of since it might be difficult to fit extre...

24 dagar ago | 0

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Creating ID using year and event number
Try this — load('sample.mat') whos('-file','sample.mat') sample count = cumsum([1; diff(sample.Var1) < 0]); ID = year(...

25 dagar ago | 0

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Smoothing or special techniques to resolve uncertain peaks are required!!
If you want to make it smooth, there are a few options. One of course is to calculate the Fourier transform, choose a suitable ...

26 dagar ago | 2

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How can I import 2D antenna radiation pattern into 2D cartesian coordinates environment?
I am not certain what you want or what your current data are. (I also do not have significant experience with the Antenna Toolb...

26 dagar ago | 0

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Hello, How can I make the output timetable look similar in the photo, so it will 901*1 instead of 901*3
You can do that once, however if you write it and then read it, it will lose the original formatting. To illustrate — Time ...

27 dagar ago | 0

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Data Organization in ECG Analysis: Separate Leads or Individual Signals
I am not certain what you want to do, or what question you are asking. In general, EKG data are analysed column-wise, with a t...

27 dagar ago | 0

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Multiple Regression and Intercept
I see nothing wrong with the code, and it conforms to the example in the regress documentation. The only suggestion I have is...

27 dagar ago | 1

Plotting Cylinder Surface Using fill3
It is easier to use the surf function for this — % figure() % theta = 0:0.5:2*pi; theta = linspace(0, 2*pi, 11); xs = [cos(...

28 dagar ago | 0

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Is the pvalue from an lmfit table derived from a two-sided or one-sided t-test?
For what it’s worth, when I updated my polyparci function, I used a default two-sided t-distribution to calculate the probabilit...

29 dagar ago | 1

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I want to solve the equation in the picture and use ode45 to solve it, but after running for 5 hours there is still no result, I would like to ask if the program is written wrong or is there any optimization?
The system is ‘stiff’ probably because of the large variation in the magnitudes of the parameters. Using a stiff solver (ode1...

29 dagar ago | 0

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Plot frequency responses based on the ODE results
I am not certain what result you want. The freqz function only works on Signal Ptocessing Toolbox filter results. To use the C...

29 dagar ago | 0

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