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PROFESSIONAL: Physician (M.D.): Diplomate of the American Board of Internal Medicine; M.Sc. Biomedical Engineering: Instrumentation, Signal Processing, Control, System Identification, Parameter Estimation

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Answered

variable thresholding for peak detection in ecg signal

I’m guessing that your signal has a wandering baseline, so MinPeakHeight is inconsistent with it. If that’s true, you can eithe...

variable thresholding for peak detection in ecg signal

I’m guessing that your signal has a wandering baseline, so MinPeakHeight is inconsistent with it. If that’s true, you can eithe...

26 Minuten ago | 0

Answered

lsqcurvefit for two different equations and variables

This works, however it only fits one of the curves: y_theo = @(x,xdata) [x(1).*(1+(x(2)./xdata).^(log10(2)/x(3))).^(-x(3)./log...

lsqcurvefit for two different equations and variables

This works, however it only fits one of the curves: y_theo = @(x,xdata) [x(1).*(1+(x(2)./xdata).^(log10(2)/x(3))).^(-x(3)./log...

etwa 2 Stunden ago | 0

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Answered

What is wrong with my filter?

‘Why is it filtering the wrong frequencies in the middle bands?’ First, the sampling frequency of your signal and the samplin...

What is wrong with my filter?

‘Why is it filtering the wrong frequencies in the middle bands?’ First, the sampling frequency of your signal and the samplin...

etwa 3 Stunden ago | 0

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Answered

How can I find rise time from an array of values that starts and ends at its steady state?

The stepinfo function will work if you have a Control System Toolbox or System Identification Toolbox ‘system’ object. It will ...

How can I find rise time from an array of values that starts and ends at its steady state?

The stepinfo function will work if you have a Control System Toolbox or System Identification Toolbox ‘system’ object. It will ...

etwa 3 Stunden ago | 0

Answered

Sampling rate in matlab

There is no default sampling rate for ifft because ifft does not actually sample anything. If the original fft is calculated co...

Sampling rate in matlab

There is no default sampling rate for ifft because ifft does not actually sample anything. If the original fft is calculated co...

etwa 6 Stunden ago | 0

Answered

fprint problem in matlab

The fprintf fuction returns the number of bytes ouitput to the file. You probably want sprintf instead here.

fprint problem in matlab

The fprintf fuction returns the number of bytes ouitput to the file. You probably want sprintf instead here.

etwa 21 Stunden ago | 0

Answered

Upgrade MATLAB from r2013b to r2017b problem.....

Much changed in those four years, specifically in R2014b and R2016b. (that introduces implicit array expansion). You now nee...

Upgrade MATLAB from r2013b to r2017b problem.....

Much changed in those four years, specifically in R2014b and R2016b. (that introduces implicit array expansion). You now nee...

etwa 21 Stunden ago | 0

Answered

Accuracy of resampling for decreasing vector size

Use the method argument to determine how the resampled vector is created. I have no idea how the other resample call returned...

Accuracy of resampling for decreasing vector size

Use the method argument to determine how the resampled vector is created. I have no idea how the other resample call returned...

etwa 21 Stunden ago | 0

Answered

How to split vector according to conditions?

One approach: V = [1 2 34 35 36 102 103 104]; d = find(diff([0 V]) > 1); p = diff([1 d numel(V)+1]); Out = mat2cell(V, 1, p...

How to split vector according to conditions?

One approach: V = [1 2 34 35 36 102 103 104]; d = find(diff([0 V]) > 1); p = diff([1 d numel(V)+1]); Out = mat2cell(V, 1, p...

ein Tag ago | 0

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Answered

How do I use ode45 to solve this ODE?

‘...all their equations have t in it.’ As does the one you posted. Note that ‘B’ is implicitly a function of time, because...

How do I use ode45 to solve this ODE?

‘...all their equations have t in it.’ As does the one you posted. Note that ‘B’ is implicitly a function of time, because...

ein Tag ago | 0

Answered

Sin and Cosine curves are coming out like zigzags

Increase ‘numSamples’. Try this: numSamples = 120; It can be anything you want (within limits). A higher number creates b...

Sin and Cosine curves are coming out like zigzags

Increase ‘numSamples’. Try this: numSamples = 120; It can be anything you want (within limits). A higher number creates b...

ein Tag ago | 0

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Answered

Error Message "Unrecognized function or variable"

Note that ‘pcaBinnedSpikes’ is assigned within an if block. If the if condition is never satisfied, ‘pcaBinnedSpikes’ will ne...

Error Message "Unrecognized function or variable"

Note that ‘pcaBinnedSpikes’ is assigned within an if block. If the if condition is never satisfied, ‘pcaBinnedSpikes’ will ne...

ein Tag ago | 0

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Answered

How to retrieve the location of the points plotted ordered

The easiest way to do that is to use the flip function (or fliplr or flipud, depending on what you want to do). Try this: f...

How to retrieve the location of the points plotted ordered

The easiest way to do that is to use the flip function (or fliplr or flipud, depending on what you want to do). Try this: f...

ein Tag ago | 1

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Answered

Plotting over a certain range, what am i doing wrong here?

Mixing radian and degree angle units makes this a bit more challenging. Try this: yfcn = @(a) sin(a) .* ((120*pi/180 < a) &...

Plotting over a certain range, what am i doing wrong here?

Mixing radian and degree angle units makes this a bit more challenging. Try this: yfcn = @(a) sin(a) .* ((120*pi/180 < a) &...

ein Tag ago | 0

| accepted

Answered

how do i create a surface around two circles of different diameters located a specific position???

You are close. You need to concatenate the vectors into matrices, then use surf to plot them. Try this: xm = [x1; x2; x3];...

how do i create a surface around two circles of different diameters located a specific position???

You are close. You need to concatenate the vectors into matrices, then use surf to plot them. Try this: xm = [x1; x2; x3];...

ein Tag ago | 0

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Answered

MarkerSize in 3D scatter plot

See Vary Marker Size in the scatter3 documentation.

MarkerSize in 3D scatter plot

See Vary Marker Size in the scatter3 documentation.

ein Tag ago | 0

Answered

How do I find the oscillation of these wobbles on matlab?

I am not certain what you want. If you want to find the predominant frequency, the best way is likely to use the fft function...

How do I find the oscillation of these wobbles on matlab?

I am not certain what you want. If you want to find the predominant frequency, the best way is likely to use the fft function...

ein Tag ago | 0

Answered

Confusion with transfer functions

They are completely different functions. The tf function defines a transfer function in the Control System Toolbox. The tf...

Confusion with transfer functions

They are completely different functions. The tf function defines a transfer function in the Control System Toolbox. The tf...

2 Tage ago | 0

Answered

need to make a function to change a high value to the average in a matrice

The fillmissing function (R2016b and later releases) may be able to do what you want. First, set the values >300 to NaN (you do...

need to make a function to change a high value to the average in a matrice

The fillmissing function (R2016b and later releases) may be able to do what you want. First, set the values >300 to NaN (you do...

2 Tage ago | 1

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Answered

"The value on the right-hand side of the assignment has the wrong width." Error

I am not certain where the problem is in the two lines you posted. Try this: idx= strcmp(station001_eus{:,10}, ',,7'); sta...

"The value on the right-hand side of the assignment has the wrong width." Error

I am not certain where the problem is in the two lines you posted. Try this: idx= strcmp(station001_eus{:,10}, ',,7'); sta...

2 Tage ago | 0

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Answered

Create month array?

Try this: t = datetime('01', 'InputFormat','MM', 'Format','MM') : calmonths(1) : datetime('12', 'InputFormat','MM'); .

Create month array?

Try this: t = datetime('01', 'InputFormat','MM', 'Format','MM') : calmonths(1) : datetime('12', 'InputFormat','MM'); .

2 Tage ago | 0

Answered

Eliminates a value less than 1 and replace with nan for all the row

What you want the result to be is not obvious. Try this: TT(ind,:)={NaN}; .

Eliminates a value less than 1 and replace with nan for all the row

What you want the result to be is not obvious. Try this: TT(ind,:)={NaN}; .

3 Tage ago | 1

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Answered

Dashed confidence intervals and xlabel

To plot as you want to plot, you need to create an ‘x’ vector to plot against. Since you are plotting against the row indices, ...

Dashed confidence intervals and xlabel

To plot as you want to plot, you need to create an ‘x’ vector to plot against. Since you are plotting against the row indices, ...

3 Tage ago | 0

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Answered

how can I set axis's tick or scale like photo.. help plz,,

Add these lines: grid set(gca, 'XScale','log', 'YScale','log', 'YLim',[0.01 100]) so the complete code is now: CD = @(Re) ...

how can I set axis's tick or scale like photo.. help plz,,

Add these lines: grid set(gca, 'XScale','log', 'YScale','log', 'YLim',[0.01 100]) so the complete code is now: CD = @(Re) ...

3 Tage ago | 0

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Answered

Why I am unable to recreate curve fitting equation?

I have no idea what the problem is. The fminsearch function had no probllem with it. The Code — f = @(b,x) b(1).*exp(b(2)....

Why I am unable to recreate curve fitting equation?

I have no idea what the problem is. The fminsearch function had no probllem with it. The Code — f = @(b,x) b(1).*exp(b(2)....

3 Tage ago | 1

Answered

QRS complex detection in ventricular tachycardia ECG

If this is a homework problem, you will not be able to use this code. If it is for research, you can likely adapt it to other p...

QRS complex detection in ventricular tachycardia ECG

If this is a homework problem, you will not be able to use this code. If it is for research, you can likely adapt it to other p...

3 Tage ago | 0

Answered

finding troughs in signal

See my Answer in: How to find QRS complex for this Graph? for one approach to this problem. You will likely need to modify tha...

finding troughs in signal

See my Answer in: How to find QRS complex for this Graph? for one approach to this problem. You will likely need to modify tha...

3 Tage ago | 0

Answered

Concatenating 2 vectors into 1 vector with the values adjacent to each other

Yes. Use datetime to create them. Example — CO2_Mtx = [2012 01 rand; 2012 2 rand; 1985 5 rand; 1985 6 rand]; ...

Concatenating 2 vectors into 1 vector with the values adjacent to each other

Yes. Use datetime to create them. Example — CO2_Mtx = [2012 01 rand; 2012 2 rand; 1985 5 rand; 1985 6 rand]; ...

4 Tage ago | 2

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Answered

How to find QRS complex for this Graph?

This is not a trivial problem. This EKG displays the Wolf-Parkinson-White syndrome, so the normal Q-wave is not present. It ac...

How to find QRS complex for this Graph?

This is not a trivial problem. This EKG displays the Wolf-Parkinson-White syndrome, so the normal Q-wave is not present. It ac...

4 Tage ago | 0

| accepted

Answered

Convert MOV to AVI file

The only option appears to be VideoWriter. Several Answers I looked through appear to indicate that it can do what you describe...

Convert MOV to AVI file

The only option appears to be VideoWriter. Several Answers I looked through appear to indicate that it can do what you describe...

4 Tage ago | 0