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.

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Storing regression coefficients in a loop
Well, not really. This instead — slopes(i,j) = slope; pvals(i,j) = pval; .

ongeveer 5 uur ago | 0

There are any number of approaches, including lowpass filters of various descriptions. Another one would be polyfit and poly...

ongeveer 6 uur ago | 0

How to plot a bode graph for a filtered output?
‘... coeffficient converted into its transfer function, [b a]=sos2tf(SOS,G).’ Do not do that! Keep it as a second-order-sect...

ongeveer 10 uur ago | 1

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How can i plot a differential setting my own sample time?
Yes. Define the ‘tspan’ argument as a vector with more than 2 elements, for example to go from 0 to 5 with 15 sampling pints,...

ongeveer 11 uur ago | 0

Filtering unwanted noise in Audio ECG Signal
The 5 Hz signal is well within the spectrum of the normal EKG (0-100 Hz), so a bandstop or other frequency-selective filter is i...

ongeveer 12 uur ago | 0

Calculate days between two given months
Use the between function — t1 = datetime('7-Dec-1941') t2 = datetime('now') ElapsedDays = between(t1,t2,'Days') ElapsedDays...

ongeveer 15 uur ago | 0

How to Remove Seasonal Cycle?
If the seasonal cycle is a narrow frequency band, and the data are sampled at consistent regular intervals, use a bandstop filte...

ongeveer 15 uur ago | 0

how do i color this?
figure rectangle('Position',[0 0 2 4],'Curvature',0.2, 'FaceColor','r') axis equal rectangle ('Position',[0.2 3 0.7 0.9],...

ongeveer 23 uur ago | 1

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how do i fill rectangle with color?
This is how — figure rectangle('Position',[0 0 2 4],'Curvature',0.2, 'FaceColor','r') .

ongeveer 24 uur ago | 0

Fit power function to data (optimization)
The problem is the model. It may not be appropriate for these data. A logistic curve fits much better — xdata = [0.02 0....

1 dag ago | 0

How to create a Stereo Sweep from Frequency A to B in a given time?
The built-in Signal Processing Toolbox chirp function is perfect for this — Fs = 1E+4; t1 = linspace(0, Fs-1, Fs)/Fs; s1 = c...

1 dag ago | 1

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How to fix the error message, "incorrect dimensions for matrix multiplication"?
I cannot run images of code, only code text. The code needs to do element-wise multiplication — x = 0:0.1:120; p = 150; e...

1 dag ago | 0

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How to get all the individuals in a table with a certain string value
See if the findgroups function will produce the desired result. .

1 dag ago | 1

Change values of the first column in a txt file
It depends on the desired result in the combined file. If they are supposed to be sequential (so that the first cxolumn in th...

1 dag ago | 0

loop calculation and skipping the numbers
The indexing is incorrect. It leaves gaps. The gaps can be eliminated with a more efficient indexing approach. This fixes t...

2 dagen ago | 0

syntax error for matrix
Typo: A = [3+2+1*s 1*s+2 -3; -s-2 2+1*s+2*s+4*s -2*s; -3 -2*s 3+(1/(2*s))+2s] ...

2 dagen ago | 1

i could not fix the error part !
The problems were that the ode23 call has to be: [t,x] = ode23(@diff2,[t0,tf],x0); so it refers to ‘diff2’ correctly as a fun...

2 dagen ago | 1

How to rearrange an equation in matlab to get the poles?
If the Control System Toolbox is available — %Values Vs = 1; Z0 = 50; R = 50; C = 1e-9; L = 0; s = tf('s'); %Where s = ...

2 dagen ago | 0

Question concerning the detection of Rate of change (positive only in this case)
First lowpass filter the signal to remove as much noise as possible. The sgolayfilt function is best for removing broadband noi...

2 dagen ago | 0

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Solving and plotting solution of 3rd order ODE using ODE45
If the Symbollic Math Toolbox is available, use the odeToVectorField function to create the appropriate array, then use matlabFu...

2 dagen ago | 0

Adding values to a matrix in for loop
Subscript ‘in’ here — values_change = values_change + in(i); and then subscript ‘values’ (the preallocation is optional, howe...

2 dagen ago | 1

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How to find baseline intensity in noisy mass spectra?
In the posted data, the baseline is not a constant, since there is a descending part at the left end (below about 150) before it...

2 dagen ago | 0

This is far past my understanding of matlab and want to understand how to code such a thing, thank you
I only see two spikes in the Fourier transformed data, one at 120 Hz and the other at 240 Hz. A FIR filter can elimiated both s...

3 dagen ago | 1

How to keep yticklabels intact after reversing the Y-axis
Just change the labels — x = linspace(0, 100); y = [20:20:80].'*exp(-(x-50).^2/75); figure plot(x, y) grid title('Ori...

3 dagen ago | 1

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Need plot for time rather than samples
If the time vector does not already exist, create it — Signal = sin(2*pi*(0:999)*0.01) + randn(1, 1000); % Create 'Signal' ...

3 dagen ago | 0

How to use coeffs to a minimum power
One approach — syms x eqn(1,:) = 5*x^2 + 2*x + 8; eqn(2,:) = 42*x^3 + 3*x^2 + 3; eqn for k = 1:numel(eqn) [cfs...

3 dagen ago | 0

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How to generate a signal using exponential forier series?
I have no idea what the Question actually is, however generating a Fourier series from disconnected lines is straightforward, if...

3 dagen ago | 0

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Nyquist and bode plots
It the System Identification Toolbox is available, start with the idfrd function and go from there. The documentation is relati...

3 dagen ago | 1

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