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# 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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How can I plot this X and Y data?

18 hours ago | 0

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how to separate a large text file into individual text files based on date, but also export headers?

20 hours ago | 0

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Is the window function automatically used when doing the fft function, or do I have to enter code to use the window function?
The fft defaults to a rectangular window that is the length of the signal. That is the only one that is ‘autoomatically’ used. ...

1 day ago | 0

Creating sounds with changing amplitude
Try this — Fs = 44100; Ft = 440; sec = 2; t = linspace(0, Fs*sec*60-1, Fs*sec*60).'/Fs; % ChkFrq = 1/t(2) s = sin(2*pi*Ft...

1 day ago | 0

How to interpret results of FFT/DFT?
The time vector needs to be scaled correctly if the frequency vector is to be correct. Try this — T1 = readtable('https://w...

1 day ago | 0

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Plot a graph from arrays
Try something like this — hv = [0,2,4,6,8]; Xm = [ {[54.8765]} {[15.8544]} {[55.3118]} {[19.0629]} {[55....

1 day ago | 0

Logical operator not evaluating correctly
Only two comparisons are actually required here — X = linspace(-7, 7, 15); Y = -(X < -5) + (X > 5); Check_Result = [X; Y] ...

1 day ago | 0

add the magnitude ratio and the phase angles data points on bode diagram
I am not certain what you want for the result. The fit is not the best, however the compare function will plot the data and t...

2 days ago | 0

How to plot a graph correctly?
I am not certain that I understand what you want to do. If you only want the contour at ‘F=0’, supply that as the fourth, ‘Le...

2 days ago | 0

How do I simplify a function?
You apparently defined some of those variables as arrays previously. To use the simplified function numerically, use the matl...

3 days ago | 0

How to covert rownames to the first variable in the table?
Try something like this — T1 = array2table(randi(9, 5, 5)); T1.Properties.RowNames = {'1','2','3','4','5'} ...

3 days ago | 0

How to calculate the derivative of vector
Fro symbolic variables, diff only works with funcitons. To calculate a numeric derivative, try something like this (assuming ...

4 days ago | 0

Ideal way to smoothe gyroscope data
The LPF approach is likely appropriate, and an IIR filter (elliptical is most efficient) is likely the best option. First, de...

4 days ago | 0

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How to remove the value using Histogram
I have only a vague idea of what you want to do, especially since the .mat file does not appear to contain the same data as depi...

4 days ago | 0

what is the correct way to write this expression in matlab?
If ‘R’, ‘L’, and ‘C’ are all arrays of the same size, use element-wise operations in every multiplication, division, and exponen...

4 days ago | 1

I'm really not good at this. "Array indices must be positive integers or logical values." What is wrong?
I suspect you want to define ‘u’ as a unit step function. This does that (and solves the ‘u’ error) however it gives a likely u...

5 days ago | 0

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How do I add rows to a table in a for loop?
The vertcat function needs to know what ‘NewRow’ is to be concatenated to. Try something like this — T1 = array2table(magic...

5 days ago | 0

time domain specifications calculations from graph
I am not certain what you want to do. Try something like this — sys = tf(4,[1 2 10]); si = stepinfo(sys); RT = si.RiseT...

5 days ago | 0

MATLAB error using fzero function
I have no idea what intersections you want to find, so this is a guess. It should at least get you started — % clear all; c...

5 days ago | 1

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How can you shift the position of x axis labels?
They’re probably text objects, however it’s not possible to access their properties. The only way to change them is to get them...

5 days ago | 0

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Unable to set the scatter3 marker color using clim
Perhaps something like this — scatter3(x, y, z, 50, z, 'filled', 'MarkerEdgeColor', 'none'); The fourth argument to scatter3 ...

6 days ago | 0

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How do I remove the tick marks on a bar plot at the top and the right?
Turn the Box property 'off', then use xline and yline to draw the lines — figure bar(rand(1,10)) Ax = gca; Ax.Box = 'off'...

6 days ago | 0

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PPG and Remote PPG peak detection
I went back to have another look at this. The two signals appear to have very little in common, even with respect to their Fo...

6 days ago | 0

latex in text doesn't work
Use two backslants (\\) in any sprintf call to ‘escape’ it — text(1, 1.5,sprintf('$\\tilde{y_x}$= %.3f',5), ... 'Interpre...

6 days ago | 0

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How to avoid determining P wave in PVC beat ?
There is no true P-deflection preceding a PVC. That is essentially the definition of a Premature Ventricular Contraction or P...

7 days ago | 0

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matlab plot legend bug
It is not possible to determine what the problem is without the data and a text (not image) version of the code. One option i...

7 days ago | 0

Error with plotting function
You will need to use element-wise operators with vector arguments. See Array vs. Matrix Operations for details. Use surf for...

7 days ago | 1

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Peak to peak amplitude

7 days ago | 0

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