Answered
High Frequency Noise baseline filter
Your data have broadband noise, so as might be expected, a frequency-selective filter is going to have very little effect. Prob...

2 years ago | 1

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Answered
How to interface symbolic solutions with numeric ode solvers
With an initially symbolic set of differential equations, the symbolic versions should not be part of a numerical integration. ...

2 years ago | 0

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How do I obtain the area of each contour on a contour3 plot?
I wrote some utility routines to get information from contour plots a while ago, and tweaked them for this project. The ap[proa...

2 years ago | 0

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How to plot direction of forces on a body with polar plots or similar?
I can’t figure out what you’re plotting. The data are vectors, so any sort of surface plot isn’t possible, and I don’t understa...

2 years ago | 1

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Answered
Can someone help me display the area bounded by the curve and the linear line. Pls see attached photo.
One approach — clear all; close all format shortG filename = 'GT+10-ubc-X-Axis - Static.csv'; T1 = readtable(file...

2 years ago | 0

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Answered
I want to find the least negative non positive number in a vector
Perhaps this — V = [-10 , -5 , -1 , -0.1 , 0 , 1 , 2 , 3 , 4 , 5] [Vmax,idx] = max(V(V<0)) V(idx) .

2 years ago | 1

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Answered
Plot Piecewise function graph
To do this in the Symbolic Math Toolbox, just write it essentially as in your original post — syms x f(x) = piecewise((-3*...

2 years ago | 0

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Surf plot from excel file
It would help to know what the data are, and what you want to do with the NaN values. That aside, just plot all but the firs...

2 years ago | 0

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How to Curvefit amplitude output of a spring-mass-damper system to find coefficients?
Try this — load('sampleData.mat') % whos objfcn = @(b,t) b(1) .* exp(b(2).*t) .* cos(2*pi*b(3)*t + b(4)) + b(5); Lvlm =...

2 years ago | 0

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Answered
Using string variable names for dot indexing
That approach can work, however it is necessary to put the variable name from the cell array in parentheses — varnames = {'rs...

2 years ago | 0

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Answered
Normalized graph not showing
The timeseries ‘out.Q_i_nd.Data’ is a 3D matrix. You need to use the squeeze function to remove the extra singleton dimensions. ...

2 years ago | 0

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I am trying to plot a graph of two variables z1 and z2 versus t. but for some values of t I am getting z2 values negative in a graph. How to make these z2 values zero?
One approach — z2 = randn(1,10) z2(z2<0) = 0 .

2 years ago | 0

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Want to truncate an array
There are a few options, including using the vpa function in the Symbolic Math Toolbox, and to use sprintf to display the values...

2 years ago | 0

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bug in sprintf 2024a, can't use other variable and just repeating the first variable
The residue funciton produces column vectors in its output. To use sprintf with them, concatenate them in a matrix and then tra...

2 years ago | 0

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Answered
Graph lines not showing
See if the yline function will do what you want.

2 years ago | 1

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Two sets of data with two date ranges and y-axis values
Try this — x1 = 1:250; y1 = 20*sin(2*pi*x1/100) + 20 + randn(size(x1))*5; x2 = 15:250; y2 = cos(2*pi*x2/150)*60 + 150 + ...

2 years ago | 1

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Answered
Parameters identification providing derivative
The differential equation needs to be integrated in order to use . This does not appear to be as straightforward as I would hav...

2 years ago | 1

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Answered
How to use values from excel file in genetic algorithm
Use the readmatrix function instead of readtable since there are no variable names. It produces a matrix that can be address...

2 years ago | 1

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Answered
How to do fft of a csv file to plot amplitude spectrum
See the documentation for both fft and nufft. One of those should apply to your problem. Another optioon is the pspectrum fu...

2 years ago | 0

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Parameter estimation of SEIHRDBP model
The time values are incorrect. The complete table of those values should be — Date Infected Death ____ ___...

2 years ago | 0

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Answered
Fitting an custom equasion where i only want to optimize specific parameters
You would need to supply pre-determined values for ‘sigk’, ‘h1’, ‘g1’, and ‘Dwir’ if you have them (you have already calculated ...

2 years ago | 1

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Grid in MIMO nyquist diagram
I am not certain what you want to do or how much of the documentation you have explored. Most of the Control System Toolbox a...

2 years ago | 1

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Fittype issue: unrealistic results and problems with upper and lower bounds
The bounds may not be set correctly. Note that while ‘a’ is supposed to be between 0.1 and 1, your bounds for it are between 10...

2 years ago | 0

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Answered
Parameter estimation of SEIHRDBP model
Thank you for quoting my code! The problem was here: c0=theta(end-3:end); use this instead: c0=theta(end-7:end); Since m...

2 years ago | 0

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Answered
unable to plot semilogy properly
The easiest way to solve that is to plot each curve on its own y-axis using the yyaxis function — % QPSK M = 8; k = log2(M)...

2 years ago | 0

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datetime don't displays the correct order
The 'InputFormat' and 'Format' name-value pairs are not the same. You need to specify them separately — aaa=datetime(dataa,...

2 years ago | 0

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How to get daily max, min, and mean from a timetable?
Your groupsummary call is correct, except for not putting the data variables in square brackets (or curly braces). With that...

2 years ago | 0

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Answered
I'm unsure of why there is an error on F=@x
The statement order is reversed from what it should be — f=@(x)exp(-0.5*x)*(4-x)-2; df=@(x)exp(-0.5*x)*(-3+0.5*x); Xs = n...

2 years ago | 1

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Answered
small floating point has been considred as zero value!
Your code works correctly when I run it here — x=0.16 if x>0.1 d=1 else d=0 end d .

2 years ago | 0

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Find Area under the curve as a non negative
It would help to have the data. Perhaps selecting everything with both x and y coordinates greater than zero, and then integr...

2 years ago | 0

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