Star Strider

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15.731 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
Want to Get Plot To Have Contunuous Angles, Not Stay between -180 and +180 Degrees
The unwrap function works on radian angle measure. I am not certain how the angles were derived, however atan2d is another o...

circa un'ora ago | 0

Answered
How do I plot fourier transform signals in Matlab
f = @ (t) exp(-abs(t)).*cos(20*t); figure fplot(f) for the Symbolic Math Toolbox, this becomes: syms t f(t) = exp(-abs(...

circa 2 ore ago | 0

Answered
How to remove spurious lines?
Sort ‘velocity’: [velocity, idx] = sort(velocity); figure plot3(Freqs,velocity,filtered(idx)) ylim([-2 0]) xlim([2.5 15]...

circa 3 ore ago | 0

Answered
Unknown variable complex equation
I ahve no idea what ‘Cp’ does here. Otherwise: gamma = 1.4; prat = @(Me,gamma) ((1+(gamma-1)/2.*Me.^2).^(gamma/(gamma-1)))...

circa 6 ore ago | 0

Answered
solve equation : Empty sym: 0-by-1
The Symbolic Math Toolbox may not be appropriate for this problem. Try this: freq = linspace(10*1e3, 31*1e6,100); w = 2*pi...

circa 8 ore ago | 0

Answered
plotting 2 variables as they change with respect to one another
The solution is to subscript ‘A’. Try this: gamma = 1.4; %M=1.53 Mv = (0.1:0.01:2.19); for k1 = 1:numel(Mv) M = Mv(...

circa 9 ore ago | 0

Answered
Divide matrix in subgroups
The mat2cell function will likely do what you want. Note that assigning each matrix to a different variable is not advisable....

circa 11 ore ago | 0

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Suggestions for financial simulation
That is an interesting problem! Use your favourite seach engine (I prefer DuckDuckGo) and search on: financial simulations usin...

circa 12 ore ago | 0

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How do I extract the amplitude and the frequency from a sine function?
Use the fft function. Calculated, interpreted, and plotted correctly, it will give all that information.

circa 12 ore ago | 0

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Returning to a function and changing variables if ans is false?
I would do something like this, and treat it as an optimization (specifically root-finding) problem, returning the value of ‘dRo...

circa 22 ore ago | 0

Answered
How to reduce the size of a graph to see the title and a legend that are not displayed?
Try something like this: figure plot( ... ) title( ... ) legend( ... ) pos = get(gcf, 'Position') set(gcf, 'Position',pos...

circa 23 ore ago | 0

Answered
Date time conversion problem
The posted code has errors. Try this: A = ['2015-01-01T19:00:00+0100' '2015-01-01T20:00:00+0100']; dates_extracted...

circa 24 ore ago | 0

Answered
overlapping two contours and defining specific lines to be compared
See the contour documentation section on levels for details. To plot contours at 18°C, that would plot as: contour(X,Y,Z, [1 ...

1 giorno ago | 0

Answered
Plotting errorbar on a set of data
I do not see ‘B’ anywhere. With ‘A’ as the matrix in the post, try this: Amean = mean(A(:,2:end),2); Astd = std(A(:,2:end)...

1 giorno ago | 0

Answered
Parameters estimation using lsqcurvefit
I did not see this originally, or I would have responded to it several days ago. The code needed some tweaks (that I will let...

1 giorno ago | 1

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Answered
Error using mesh z must be a matrix
The arguments to ‘z’ need to be matrices in order for ‘z’ to be a matrix. Use ndgrid or meshgrid (linked to on that page) to cr...

1 giorno ago | 0

Answered
How to represent continuous time Transfer function in a script
(1.) Correct! (2.) No.

2 giorni ago | 1

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Answered
How to fill plot between two lines
If I understand the objective correctly, this should work: DL = load('data1.mat'); data = DL.data; max=plot(data(:,1),data...

2 giorni ago | 0

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Answered
System Identification impulseset function: how do I avoid using deprecated features?
The iddata call contains all the time information the identification functions need in order to estimate the system, in the arra...

2 giorni ago | 0

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Answered
Fit log10 function to data and determine the intercept
If ‘b’ is the y-intercept, the easiest way is to interpolate: x = [0.24, 0.6, 1.2, 2.4, 6, 12, 24]; y = [17.2499, 9.8872, 5.6...

2 giorni ago | 0

Answered
Nth order Butterworth low pass filter design
Since in radian measure the frequency is defined on the interval , and 1 is obviously in that interval, use 1 as ‘Wn’, since tha...

2 giorni ago | 0

Answered
how to normalize EKG/ ECG signal
See if the rescale function (introduced in R2017b) will do what you want.

2 giorni ago | 0

Answered
using 'controlchart' and 'findpeaks'
That is going to be something of a challenge, however it is possible. Using an example from the controlchart documentation: ...

2 giorni ago | 0

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Answered
2D line graph plotting from calculations
There are too many missing variables for me to run the code, however consider doing something like this: k = 1; ...

2 giorni ago | 0

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Limits on a line plot
It may simply be necessary to ‘stretch’ the figure. Try something like this: pos = get(gcf, 'Position'); set(gcf, 'Positio...

2 giorni ago | 0

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Answered
Remove rows from table identified in a second string array
The ismember function would likely work, however the two tables you want to compare have nothing in common in the variables you ...

2 giorni ago | 1

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Answered
amplitude and phase spectrum
No idea what the sampling frequency is, so I created one. Try this: Fs = 600; t = linspace(0, Fs*10, Fs*10)/Fs; x=8*cos(3...

2 giorni ago | 1

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Answered
High Pass Filter Error
The problem may be with ‘u_G_Interp’, and since we do not have it to work with, we cannot determine that. Assuming it is a do...

2 giorni ago | 0

Answered
Add data on matlab graphs
Use a text object, or put it in the appropriate axis label: t = 0:0.1:15*pi; x = exp(-0.05*t).*cos(t); y = exp(-0.05*t).*sin...

2 giorni ago | 1

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Answered
Cannot find solution with dsolve but I know that a relatively simple solution does exist
The dsolve function apparently does not integrate nonlinear differential equations. This is likely the best you can hope for:...

3 giorni ago | 0