Community Profile # Star Strider

Last seen: Today Active since 2012

Hic sunt dracones! PROFESSIONAL: Physician (M.D.): Diplomate of the American Board of Internal Medicine; M.Sc. Biomedical Engineering: Instrumentation, Signal Processing, Control, System Identification, Parameter Estimation NON-PROFESSIONAL: Amateur Extra Class Amateur Radio Operator; Private Pilot, Airplane Single Engine Land, Instrument Rating Airplane; Gamer NOTE: I do not respond to emails or personal messages, unless they are about my File Exchange contributions. Time Zone: UTC-7 (Standard); UTC-6 (Daylight Savings/Summer)

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fft of a signal
You need to normalise the fft result by the length of the signal: X_fft = fft(y1,nfft)/L; Otherwise, using my test signal, it...

18 hours ago | 0

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Smoothing data with sgolay filter
The default order for the 'sgolay' option is 2 (quadratic), however the 'SmoothingFactor' controls the window length (framelen ...

20 hours ago | 0

How can I draw the transfer function spectra by matlab?
The ‘spectrum’ is the Bode plot: z = tf('z'); H = 5 / (1 + 2*cos(5)*z^-1 + z^-2); H.Variable = 'z^-1' figure bodeplot(H)...

1 day ago | 0

Find the relaxation Time from data set
See my latest Comment in find fitting equation and parameters to fit damped oscillations curves from set of data.

2 days ago | 0

sums up the same rounded numbers in 5-digit decimal arithmetic in n = 10, 9, 8, ..., 3, 2, 1
See the documentation for colon, : and go from there.

2 days ago | 0

how to avoid getting 0 overlap on the pie chart?
The code was not returning the correct position vectors. I am not certain what you want to do. This repositions the ‘5%’ t...

2 days ago | 0

contour() function plots with a solid background (and not a transparent background, which is desired)
Perhaps something like this — [X,Y,Z] = peaks(50); figure surf(X,Y,Z, 'EdgeColor','none') hold on contour3(X, Y, Z, 'Col...

3 days ago | 0

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How to plot bode?
We need to know more. If you have the Control System Toolbox (or the System Identification Toolbox, or both) licensed and ins...

3 days ago | 0

The upsample function is not working R2022b
I can find two upsample functions in the online documentation, one in the Signal Processing Toolbox (that should work with your ...

3 days ago | 0

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Putting measurement unit and origin in plot
I am not exactly certain what you want, however the xlim and text functions would likely be appropriate.

3 days ago | 0

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Can anyone please tell me how to plot this graph?
Use the polarplot function. It should do evertything you want. For details see PolarAxes Properties and perhaps also Line Pr...

3 days ago | 1

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bode magnitude producing different plots for the same transfer function
The upper plot is plotted with a linear magnitude and the lower one is plotted with the magnitude in decibels.

3 days ago | 0

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Extract data points from bodemag plot
it would likely be easier to use the approach bode in Obtain Magnitude and Phase Data. (Remember to use the squeeze function wi...

3 days ago | 0

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Add axes x and y labels (or title) to a scatter plot, not using tbl notation
Delete the equal sign in the xlabel, ylabel, and title calls — A_full = rand(1,570); B_30_channels = rand(1,570); figure ...

3 days ago | 1

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Fix the random values
The rng function controls the seed. Example — rng(1) r1 = randi(9,1,10) rng(1) r2 = randi(9,1,10) There are a numbe...

4 days ago | 0

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How can I get a bode magnitude to be a certain size vector?
The bode function allows you to specify a vector of frequencies in radians/time_unit.. See the documentation section on Bode Pl...

4 days ago | 0

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How can I compute envelope for three phase current?
I am not certain what you want. Perhaps this — Fs = 0.0001; t = linspace(0, 1, 1/Fs)/Fs; s = sin(2*pi*t*60 + deg2rad([0; ...

4 days ago | 0

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how can i save my values of u into a vector, so i have the result of all the u-values.
The loop is not necessary. Just use matrix multiplication. One approach — x=(0:0.1:1).'; ...

4 days ago | 1

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find fitting equation and parameters to fit damped oscillations curves from set of data
I can approximate the fit, however not to the oscillations. The best model is a mathematical model of the process that create...

5 days ago | 0

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Solve system of equations
Solve the first equation for and then plot both of them as functions of using the hold function.

6 days ago | 0

Best Fit Line for Parabola
Try something like this — x = [0; 0.019; 0.036]; y = [0.015; 0.25; 0.05]; p = polyfit(x, y, 2) xv = linspace(min(x), max(x)...

6 days ago | 0

vpasolve accuracy in two equations with two variables
I am not certain what problem you are having. One option is to solve the equations and then use vpa on the solutions. Exam...

6 days ago | 0

How to find the maximum value by comparing 2 cells?
This is not as efficient as I would like it to be, however it works — A = {2,4,5}; B = {1,10}; MaxC = max(cellfun(@(x)max([x...

6 days ago | 0

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Finite Impulse Response filter
I thought about doing this with an optimisation funciton, however it minimises the distance between the estimated transfer funct...

6 days ago | 0

FIR_Filter Kaiser
I am not certain what the problem is. Try something like this — fsamp = 12000; %sampling rate fcuts = [1800 2000]; %indic...

6 days ago | 0

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How to find monthly average from daily data?
You will need to combine the year, month, and day into one datetime array, and then replace the individual variables with the da...

6 days ago | 0

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When calling a user defined function, MATLAB throws an error for simple matrix multiplication
It is best to not use global variables. The problem is that they have to be defined in the calling routine as well as the funct...

7 days ago | 1

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How can I get txtscan to read this file?
It would help to have the file to experiment with. If textscan is only reaidng the first line, consider adding: 'EndOfLine'...

7 days ago | 0

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Can't generate histfit subplot (error using histfit, subscripting into a table)
The error is in the histfit code at line 69. That reference has nothing to do with your code or data. The problem is likely ...

7 days ago | 0

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