Star Strider

Last seen: Today

14.165 total contributions 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

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Answered
Solution of natural frequency equation with fzero function
The fzero function is likelly not appropriate here. I would instead use fsolve, and convert the obsolete inline call to an anon...

27 minutos ago | 0

Answered
a problem with power spectrum calculation (FFT)
The mean of ‘data’ is -16657.4418730469. This is the D-C component, so it appears at 0 Hz, and completely prevents the details ...

alrededor de 1 hora ago | 0

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Answered
Comapring Values in one Matrix to another
Another approach: A = [373 383 393 403 413 420 451 485 499]; B = [373 453 457 461 464]; C = ones(numel(B),1)*A; ...

alrededor de 3 horas ago | 0

Answered
How to mark the maximum points in mesh
Add this loop just before the mesh call: for k = 1:size(Response_amp,1) [Ramax(k),Idx(k)] = max(Response_amp(k,:)); ...

alrededor de 5 horas ago | 0

Answered
plot curve in matlab
syms qa h = (611375/279 - ((192500000*cos(qa))/93 + ((60000*cos(qa))/31 - 611375/93)^2/9 - 14656250/31)/(2*((153125000000*cos(...

alrededor de 5 horas ago | 0

Answered
I need to find the angle from horizontal that tangents to a curve make for multiple points
I am not certain what you want to do, or the result you want. The easiest way to calculate numerical derivatives is to use th...

alrededor de 18 horas ago | 0

Answered
Interpolation to find harmonics from fft
Consider increasing the frequency resolution by using a longer fft. That may make it easier to detect the harmonics where you e...

alrededor de 22 horas ago | 0

Answered
Reading Files and plotting in matlab
I am not certain what the responses to the input calls should be, so I did not run your code, only looked at it. It appears ...

1 día ago | 0

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Answered
system of nonlinear equation
That is not going to woork with fsolve for a number of reasons. It is necessary to convert ‘f’ to a numeric (not symbolic) fu...

1 día ago | 0

Answered
Variables under the same name in different .mat files
Use load to load each of the files into a different structure. See Load List of Variables into Structure Array. You can then...

1 día ago | 0

Answered
Looking for documentation explaining M.' and other symbols to select data from an array
‘M. means the same as M(:,:)‘ No, not ‘M.’. The extra dot will throw an error. I am not certain what you are asking. S...

1 día ago | 0

Answered
Creating a vector of datetimes with increments of 15 minutes
Try this: Timestamp = (datetime('2020-06-30 23:45:00') : -minutes(15) : datetime('2015-01-01 00:00:00')).'; Timestamp.Format ...

1 día ago | 0

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Answered
simple question of creating a time vector
Without the exact details of your file (that I suspect is not exactly 60 seconds long), something like this will work: t = lin...

1 día ago | 0

Answered
different sound file times
If you want all of the sound files to have the same sampling frequency, use the Signal Processing Toolbox resample function. On...

2 días ago | 0

Answered
There is something wrong in R.
The problem is in the way you call the exp function. This works: R = ((2.*h).*(f.^3))./((c.^2).*(exp(h.*f/(k.*T))-1)); .

2 días ago | 1

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Answered
Plot AREA limit in matlab
If you want the area between ‘abb_per’ and 100 filled, use the patch function. Try this: figure patch([n fliplr(n)],[abb_p...

2 días ago | 0

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Answered
lowpass() not working
A low passband with a very high sampling frequency is asking a lot of any filter. I am somewhat surprised that lowpass used a F...

2 días ago | 0

Answered
How to plot 3D surface with vector-input function?
The function you coded: FUN = @(x) = x(1).^2+x(2).^2; will only take the first 2 elements of ‘x’ (whatever it is), and will r...

3 días ago | 0

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Answered
piecewise for use in anonymous functions
One option: Rt0 = @(theta,theta1,theta2,B,H,L1) ((0<=theta) & (theta<theta1)).*(B./2+L1)./cos(theta) + ((theta1<=theta) & (the...

3 días ago | 1

Answered
extract mth and m+1st largest element from a vector
‘Is using sort is the best way?’ Yes.

3 días ago | 0

Answered
How to write a multi line string?
Since ‘tran_models’ is an array, just use a loop: for k = 1:size(tran_models,1) fprintf(File,'%s\n', tran_models(k,:)); ...

3 días ago | 0

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Answered
How can I plot and reach to this figure ?
birthday = datenum(year, month, day); t = 0:ceil(datenum(now)-birthday); Physical = sin(2*pi*t/23); The rest would be calcula...

3 días ago | 0

Answered
Solving the Kinetic equations by Matlab coding
Try this: % % % k(1) = R_Inf, k(2) = k R1fcn = @(k,t) k(1).*(1-exp(-k(2).*t)); R2fcn = @(k,t) k(1).*(1 - (1-exp(-k(2).*t))...

3 días ago | 0

Answered
Changing scientific notation to long format
Select an appropriate option (such as long g) with the format function.

3 días ago | 0

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Answered
Plot fft and peaks on same plot
You did not provide ‘x’ or any of the parameters (such as ‘Fs’) so it is not possible to run your code, and you could easily hav...

3 días ago | 0

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Answered
How to repeat the same graph?
Try this: t = 0:40; y = exp(-0.385*t) + 10; y6 = repmat(y, 1, 6); t6 = 0:numel(y6)-1; figure plot(t6, y6) grid produc...

3 días ago | 0

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Answered
How to do segmentation on ECG signal for feature extraction
Use the Signal Processing Toolbox buffer function. Calculating ‘n’ is straightforward: n = 10 * 250 producing: n = ...

3 días ago | 1

Answered
Toolbox of Genetic Programming
Download and install the Global Optimization Toolbox. Simple genetic algorithm code is relatively easy to write. It does not...

3 días ago | 0

Answered
how to plot 2 curve with together
First, use element-wise multiplication and division: m=0:0.01:50; f= ((7*m - 7*(m.^2 - (226*m)/7 + 15009/49).^(1/2) + 127)...

3 días ago | 1

Answered
If statement for input value
I would just use a loop: n = input('how many ingredients do you have'); %%FOOD INPUT for k = 1:n a(k) = input(sprintf('...

3 días ago | 1

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