Answered
How can I calculate a mean value of peak amplitude and area under the curve?
It always helps to have a signal to work with, so I found one from a previous pulse-plethysmograph post and am using it here. (...

3 years ago | 1

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Answered
Clarification of frd(response, frequency) inputs for SISO system
It would be helpful to know the context. That specific syntax does not appear to be valid for the frd function, at least to d...

3 years ago | 0

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Answered
Error bars and legend order inconsistent?
It is difficult to follow your code. Perhaps something like this — plot(x,Norm_Opt{j},'Color',cmapUS(((US_Factor(nUS)/US_Fa...

3 years ago | 0

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Finding peaks greater than a set value
‘Any ideas?’ Yes. None of the identified peaks meet the criteria you set. See my latest Comment to your earlier post How ...

3 years ago | 0

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how to add arrow on phase portrait
Use the quiver function — to = 0; tf = 30; tspan = to:0.1:tf; plotArrows = @(m) quiver(m(:,1), m(:,5), gradient(m(...

3 years ago | 0

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Answered
if statement inside of a Function is working only in certain conditions
I would just set this up as an anonymous function — capacitorVoltage = @(t) 5*(t<0); t=-2:0.2:5; v_c=capacitorVoltage(t)...

3 years ago | 2

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Finding peaks with a set amplitude range?
‘It just returns a bunch of zeros even though I told it not to. Any ideas?’ It may seem that a logical vector is returning ze...

3 years ago | 0

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Superimpose three solutions onto a direction field
Use the hold function to plot m,ore than one set of data on an axes. I do not know what the second one is, however this will ...

3 years ago | 0

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Integral from 0 to inf with imaginary numbers takes too long
First, the Symbolic Math Toolbox is not going to be as efficient as direct numerical calculations. Second, you never told the...

3 years ago | 0

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Find phase plot between input and output experimental data?
I am not certain what function created that plot (it might have been the System Identification Toolbox bode function.) See if...

3 years ago | 0

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Symbols in a transfer function:
The Control System Toolbox functions require numerical values. It is possible to create an anonymous function with your code,...

3 years ago | 1

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New to filter design: Designing filters at very low frequencies (mHz) on logarithmic frequency scale
It is quite common for a transfer function implementation to be unstable. The solution is to use zero-pole-gain output from the...

3 years ago | 0

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How can I rewrite this to get peak locations?
The locations are the second output from findpeaks, so I doubt that arrayfun will do what you want. I would do something like...

3 years ago | 0

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Problem with Fourier Transform fft
The ‘Time’ vector is not uniformly sampled. Most signal processing techniques require regularly-sampled vecttors, so I used the ...

3 years ago | 0

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Answered
Best fit of 4 points with three coordinates (x, y, z)
One approach — x= [-11.94, -14.8525, -25.0775, -45.3375]; y= [0, -0.47195, -0.52887, -87.44586]; z= [0, -2.86065, -3.04815, ...

3 years ago | 0

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What is the most efficient way to "reverse" interpolate a 3D array?
The loop would likely not be necessary interpolationg with the scatteredInterpolant function. Pass all the ‘_target’ values as ...

3 years ago | 0

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Monod nonlinear regression solved with Ode45
See: Monod kinetics and curve fitting . It could possibly work with your data. Note — As posted, ‘S’ has 21 elements, ho...

3 years ago | 1

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colormap does not work on histogram2
That is not possible with histogram2, however it is with histcounts2 and bar3 — X = randn(1000,1); Y = randn(1000,1); [N,...

3 years ago | 0

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Answered
How to transform the normalized values of a histogram (i.e. the bars heights) in percentages?
Altering the histogram plot is likely not possible because the ‘Values’ vector is read-only. The easiest approach is likely t...

3 years ago | 1

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Answered
Patch function doesnt shade the second plot.
One of those vectors in the second plot likely has at least one NaN value. Try something like this — meanNDtest = fillmissi...

3 years ago | 1

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Answered
I am getting incorrect FFT values
The 1.86 value is correct. Look at the time domain plot — %FFT T=0.01; %cuz the time interval is 0,01. You can see in "t" ...

3 years ago | 0

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Answered
Solve a system of 3 second order equations
This should get you started — syms c_1 c_2 k_1 k_2 k_n k_nl J_1 J_2 J_n theta_1(t) theta_2(t) theta_n(t) theta_out(t) t Y d1...

3 years ago | 0

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mesh or surf from x y z coordinates
I am not certain what you want. One approach — LD = load(websave('swarm','https://www.mathworks.com/matlabcentral/answers/u...

3 years ago | 0

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Answered
Fill light gray color between two horizontal lines in a plot?
To plot a ‘dash-dot¹ line requires a slightly different LineStyle definition — x=[1:10]; y=[1:10]; figure(1) plot(x,y,'b') ...

3 years ago | 0

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Answered
I Want to solve system of three differential equations numerically. How can i solve it with ode45, or are there any other ways?
syms v1(t) y1(t) y2(t) v2(t) a2(t) phi(t) L r A B C D E F G H I J beta Omega(t) Omegaac(t) omega(t) omegaac(t) Y t sympref('...

3 years ago | 0

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Answered
import data from csv and plot it
I opened it in Excel, did a straightforward manual copy-paste to Notebook, and saved it to a text file (that I uploaded here). ...

3 years ago | 1

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x values when taking a numerical derivative
‘I think (correct me if I'm wrong) this can be done by diff(y)./diff(x)’ Not actually wrong, simply mistaken with respect to ...

3 years ago | 0

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Answered
Plotting surface tangent to surface plot
The code defines ‘x’ as a scalar: x=linspace(-9,0.5,1); with one element equal to 0.5. That creates ‘X’ and ‘Y’ as vectors...

3 years ago | 0

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How do I change a date in a cell into three cells in MatLab xlsx file?
After using readtable to import the Excel file, try something like this — T1 = table(datetime('now') + days(0:4).', rand(5,1),...

3 years ago | 1

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Answered
How can i find the co-ordinates of a point where the slop is -1 in below graph ?
Try this — T1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/1285050/cmos.txt', 'VariableNamingRu...

3 years ago | 2

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