Answered
How to calculate the duration of data points in days
Try something like this — Data = readmatrix('https://www.mathworks.com/matlabcentral/answers/uploaded_files/772213/pulses.txt'...

5 years ago | 0

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Answered
Error in ode45 (line 115) and odearguments (line 90)
There were two errors. First: dydt(2)=y(2)*(1-y(2))*((y(1)*(or*rr-br*re)-ar*rr); ↑ ← EXTRA UNMATCHE...

5 years ago | 0

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Answered
How to avoid using a loop here?
One approach — N = 5; tic [m,n] = ndgrid(1:N); A = 2*N + 1 - (m + n) toc Compare — tic A = zeros(N); for m = 1:N ...

5 years ago | 0

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Answered
Timeformat from HH:MM:SS to HHMMSS
Try this — time = datetime('12:30:00', 'InputFormat','HH:mm:SS', 'Format','HHmmSS') .

5 years ago | 0

Answered
Replace comma with dot after fopen
For MATLAB versions R2019a and later, the readmatrix function permits definition of the 'DecimalSeparator' (see the Text Files O...

5 years ago | 0

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Answered
How to solve an ODE calculating the value of a variable inside a loop?
The problem is: x0 = X(end); so the error only occurs after the first iteration. The solution is: x0 = X(end,:) and thi...

5 years ago | 1

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Answered
how can I get the following graph from this data, changes are required in the code
Try something like this — T1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/771138/G2_A.txt', 'Va...

5 years ago | 0

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Answered
How can i make my ODE graph make sense?
The fplot call is incorrect, and the function declines so quickly that it’s not possible to see it clearly with a time interval ...

5 years ago | 1

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Answered
Is it possible to save ECG waveform data as an text file with RR-intervals?
I am not certain what the desired result is. Try this — EKGsig = readmatrix('https://www.mathworks.com/matlabcentral/answer...

5 years ago | 0

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Legend not matching the data
It is possible to label the individual plots in the plot calls. See Specify Legend Labels During Plotting Commands for detail...

5 years ago | 0

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Answered
Solving system of coupled ode using ode45
The NaN values are the result of the initial conditions all being 0. With a bit of cheating (setting the initial conditions all...

5 years ago | 0

Answered
Torque ripple plot in MATLAB
Try something like this — t = linspace(0, 720, 1000); s = [sind(2.5*t); sind(2.5*t+180)]; figure plot(t,s, '--') hold ...

5 years ago | 0

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what changes are needed
Try this — F = openfig('Manav Divekar untitled.fig'); F.Visible = 'off'; % Don't...

5 years ago | 0

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How to create a table to show the results of a function code?
Subscript the variables so they are column vectors, then put them in the table and return the table as one of the outputs (or pe...

5 years ago | 0

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Answered
Function keeps running into errors when I call it
Try this instead — hpeakt = sorteddata.data(:,1); wpeakt = sorteddata.data(:,5); [phivalues] = findphases(wpeakt,hpeakt)...

5 years ago | 0

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Answered
converting sym function to string MATLAB
Try this — syms x y eqn = x^2+2*x*y+3*y^2; partial_eqn = diff(eqn, x); fprintf("The partial derivative of %s w.r.t. x is...

5 years ago | 3

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Answered
Use results in the definition of my functions
Try this instead — function pv=p(X,x) pv=X(1)*x.^2+X(2)*x+X(3); end Here, ‘X’ are the parameters and ‘x’ is the variabl...

5 years ago | 0

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Answered
Could someone please explain me this code?
That looks like something I wrote! It would be helpful to know the context (I don’t remember where I posted it), however it a...

5 years ago | 1

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Answered
Integrating a 2nd order ODE
This is a boundary value problem. Use bvp4c to solve it. syms y(x) x L Y q(x) = 2*cos(pi*x/L); Dy = diff(y); D2y = diff(...

5 years ago | 0

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Answered
How can I call half of text by using "textread" ? (1*4096 matrix to 1*2048 matrix)
I have never used textread, however that could be described in the format string, for example — formatStr = [repmat('%f',1,204...

5 years ago | 0

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Answered
my fminsearch function doesn't get the optimum values
The fminsearch function searches for a minimum. To get a maximum, negate the function — [x,fval] = fminsearch(@(x)-tut2(x),[1...

5 years ago | 1

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Answered
plotting a for loop returns Empty Graph
I’m not certain what you want, however it is necessary to subscript the varialbes to be plotted. This runs without error and ...

5 years ago | 0

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Area between three curves
Try this — I created the comparisons as ‘>=’ so change those to simply ‘>’ ito make the comparisons strictly ‘greater than’. ...

5 years ago | 0

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Hi, I want to know knee point of a curve including the process of by 2nd derivative. Can anyone help by creating the script.
Use the gradient function to calculate the numerical derivative — x = linspace(0, 10); y = exp(-0.1*x) .* sin(x); D1 = g...

5 years ago | 0

Answered
I have to use Fourier Transform without frequency range?
One approach — A = [1 0.43 0.95]; B = [0.97 0.43 0.97]; [h,t] = impz(B,A); figure subplot(2,1,1) plot(t, h) grid ...

5 years ago | 0

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Answered
Turn multiple columns into one column
The code is a bit difficult to follow. I’m guessing here that you want to save the ‘allfrequency’ vectors. allfrequency(s,:)...

5 years ago | 0

Answered
To find the average of values in matrix
Try something like this (assuming that they are stored as elements of a cell array similar to these) — C = {randn(131,160), ra...

5 years ago | 0

Answered
Index exceeds the number of array elements in ODE using anonymous function
There’s a typo: 1/L13*(x(24) - (x(30)/C15 + (x(25) - x(31))*R1) - x(25*RL13)); ...

5 years ago | 0

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Answered
Incorrect datatype when using 'retime' function
The retime function works only with timetable arrays, to the best of my knowledge. See if using the table2timetable funciton fi...

5 years ago | 0

Answered
Bug in equality checks? 28.15e-3 == 28.15/1000 false
Wellcome to the world of floating-point approximation error! See Why is 0.3 - 0.2 - 0.1 (or similar) not equal to zero? and...

5 years ago | 1

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