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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

How to make rectangular train?

See if the pulstran function will do what you want.

How to make rectangular train?

See if the pulstran function will do what you want.

6 hours ago | 0

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Answered

How to do a surface plot with tangent plane?

I believe the problem is that you need to vectorise the function, using element-wise operations in the multiplications and divi...

How to do a surface plot with tangent plane?

I believe the problem is that you need to vectorise the function, using element-wise operations in the multiplications and divi...

7 hours ago | 0

Answered

add text to value of a plot, part 2

That needs a different approach. Try this: x = 1:10 y = rand(1,10); figure plot(x, y) xt = get(gca, 'XTick'); xtklbl...

add text to value of a plot, part 2

That needs a different approach. Try this: x = 1:10 y = rand(1,10); figure plot(x, y) xt = get(gca, 'XTick'); xtklbl...

8 hours ago | 0

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Answered

what is the error "must return a column vector."

The ODE function must return a column vector. I have no idea what ‘I’ is, however defining it as I do here, the code runs witho...

what is the error "must return a column vector."

The ODE function must return a column vector. I have no idea what ‘I’ is, however defining it as I do here, the code runs witho...

14 hours ago | 0

Answered

add text to value of a plot

if you have R2016b or later, use the xtickformat function to do what you want. Example — x = 1:10 y = rand(1,10); figur...

add text to value of a plot

if you have R2016b or later, use the xtickformat function to do what you want. Example — x = 1:10 y = rand(1,10); figur...

16 hours ago | 0

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Answered

Plotting multiple repetitions in one graph

See for example: Positioning a cutted signal from a ECK Signal since that EKG signal is reasonably close to the sort of signal y...

Plotting multiple repetitions in one graph

See for example: Positioning a cutted signal from a ECK Signal since that EKG signal is reasonably close to the sort of signal y...

19 hours ago | 0

Answered

Problem with bsxfun and custom function

This runs without error: A = rand(4) B = randn(5) bsxfun(@na_div,A,B) function[out] = na_div(x,y); if isnan(x) & ~i...

Problem with bsxfun and custom function

This runs without error: A = rand(4) B = randn(5) bsxfun(@na_div,A,B) function[out] = na_div(x,y); if isnan(x) & ~i...

22 hours ago | 0

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Answered

Local smoothing of peaks for a matrix

If you have R2018b or later, see if the rmoutliers function will do what you want.

Local smoothing of peaks for a matrix

If you have R2018b or later, see if the rmoutliers function will do what you want.

22 hours ago | 0

Answered

Help me undersandand Frequency Vector and index vector in fourier transform

That is my code, so I will do my best to explain it. The frequency vector ‘Fv’ here defines the frequencies for a one-sided F...

Help me undersandand Frequency Vector and index vector in fourier transform

That is my code, so I will do my best to explain it. The frequency vector ‘Fv’ here defines the frequencies for a one-sided F...

1 day ago | 0

Answered

Why are the lines not showing up on my graphs?

You are only plotting one point (that being the last point) and it is not possible to plot lines with only one point. Try thi...

Why are the lines not showing up on my graphs?

You are only plotting one point (that being the last point) and it is not possible to plot lines with only one point. Try thi...

1 day ago | 1

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Answered

how to plot line with dots?

There are several options: x = 1:10; y = rand(1,10); subplot(3,1,1) plot(x, y, '-ok') title('Circles and Lines') subplo...

how to plot line with dots?

There are several options: x = 1:10; y = rand(1,10); subplot(3,1,1) plot(x, y, '-ok') title('Circles and Lines') subplo...

1 day ago | 0

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Answered

how can I present histogram as line plot

Set DisplayStyle to stairs.

how can I present histogram as line plot

Set DisplayStyle to stairs.

1 day ago | 0

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Answered

how to model kinetic reaction system

There are several examples on fitting differential equations to data in Answers. See: ODE and Data fitting and Parameter Estima...

how to model kinetic reaction system

There are several examples on fitting differential equations to data in Answers. See: ODE and Data fitting and Parameter Estima...

1 day ago | 0

Answered

Applying sgolay filter (derivatives) on data with variable Fs

Every signal processing technique that I am aware of (except the newly-introduced nufft function) requires uniformly-sampled sig...

Applying sgolay filter (derivatives) on data with variable Fs

Every signal processing technique that I am aware of (except the newly-introduced nufft function) requires uniformly-sampled sig...

2 days ago | 0

Answered

System of nonliner equations with symbolic variables

The code needs a few adjustments: syms lamT lamZ eqT = 10*lamT^13*lamZ^13 - 10/lamT^13 - 10*lamT^2*lamZ; eqZ = 10*lamT^13*l...

System of nonliner equations with symbolic variables

The code needs a few adjustments: syms lamT lamZ eqT = 10*lamT^13*lamZ^13 - 10/lamT^13 - 10*lamT^2*lamZ; eqZ = 10*lamT^13*l...

3 days ago | 0

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Answered

Is it possible to save a workspace when a program is paused without it ending the program?

Using the save function at appropriate places in the code will not cause the code to crash. See: How to save data from Geneti...

Is it possible to save a workspace when a program is paused without it ending the program?

Using the save function at appropriate places in the code will not cause the code to crash. See: How to save data from Geneti...

3 days ago | 0

Answered

'LSQCURVEFIT requires all values returned by functions to be of data type double' error

It took a bit of effort to figure out what you are doing, and get your code to run correctly, although it still needs for you to...

'LSQCURVEFIT requires all values returned by functions to be of data type double' error

It took a bit of effort to figure out what you are doing, and get your code to run correctly, although it still needs for you to...

3 days ago | 0

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Answered

How to plot a symbolic equation

Using piecewise (R2016b and later versions) may be an option.

How to plot a symbolic equation

Using piecewise (R2016b and later versions) may be an option.

3 days ago | 1

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Answered

summation of 2 Sine waves

It does show a straight line at zero. Look at the magnitude of the y-axis (±2E-15), and you will see that it is essentially plo...

summation of 2 Sine waves

It does show a straight line at zero. Look at the magnitude of the y-axis (±2E-15), and you will see that it is essentially plo...

3 days ago | 0

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Answered

How can I create this image?

Try this: [X1,Y1,Z1] = cylinder; X2 = bsxfun(@times, X1, [1.2; 0]); Y2 = bsxfun(@times, Y1, [1.2; 0]); figure Ax = gca; ...

How can I create this image?

Try this: [X1,Y1,Z1] = cylinder; X2 = bsxfun(@times, X1, [1.2; 0]); Y2 = bsxfun(@times, Y1, [1.2; 0]); figure Ax = gca; ...

4 days ago | 0

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Answered

Sampling Audio at 11025 sample/sec in MATLAB

See: Record and Play Audio for a full description of the process. Note that SampleRate defines the sampling frequency.

Sampling Audio at 11025 sample/sec in MATLAB

See: Record and Play Audio for a full description of the process. Note that SampleRate defines the sampling frequency.

4 days ago | 0

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Answered

I'm unable to derive a function with decimals

Use the vpa function: vpa(diff(Y)) .

I'm unable to derive a function with decimals

Use the vpa function: vpa(diff(Y)) .

4 days ago | 0

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Answered

Find missing dates from a file

Try this: fidi = fopen('Dates.txt'); D = textscan(fidi, '%{dd/MM/yyyy}D') fclose(fidi); AllDates = (D{1}(1):caldays(1):D{1}...

Find missing dates from a file

Try this: fidi = fopen('Dates.txt'); D = textscan(fidi, '%{dd/MM/yyyy}D') fclose(fidi); AllDates = (D{1}(1):caldays(1):D{1}...

5 days ago | 0

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Answered

Help with some fft problems, can't come up with a better title

You need to force the index arguments to be integers. One option: plot(Y(1:fix(length(Y)/2))); There are others, dependin...

Help with some fft problems, can't come up with a better title

You need to force the index arguments to be integers. One option: plot(Y(1:fix(length(Y)/2))); There are others, dependin...

5 days ago | 0

Answered

How can I change the radius of the spiral so it varies along the length from 0 to 1?

Change ‘x’ and ‘z’ to: x=cos(y/100*10*pi).*(y/100); z=sin(y/100*10*pi).*(y/100); so the full code siis now: y=0:0.5:100; ...

How can I change the radius of the spiral so it varies along the length from 0 to 1?

Change ‘x’ and ‘z’ to: x=cos(y/100*10*pi).*(y/100); z=sin(y/100*10*pi).*(y/100); so the full code siis now: y=0:0.5:100; ...

5 days ago | 0

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Answered

How to get spectrogram of an array in MATLAB?

The documentation states that the input signal is ‘specified as a row or column vector’, so you would need to loop through each ...

How to get spectrogram of an array in MATLAB?

The documentation states that the input signal is ‘specified as a row or column vector’, so you would need to loop through each ...

5 days ago | 0

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Answered

Why can't I automatically get an integer from this simple function?

You have encountered floating-point approximation error. See Floating-Point Numbers for an extended discussion. The differen...

Why can't I automatically get an integer from this simple function?

You have encountered floating-point approximation error. See Floating-Point Numbers for an extended discussion. The differen...

5 days ago | 0

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Answered

How can I find integral of a 3-D mesh field?

See if using trapz on one or both dimensions of your matrix will do what you want.

How can I find integral of a 3-D mesh field?

See if using trapz on one or both dimensions of your matrix will do what you want.

5 days ago | 0

Answered

Executing a multiple plot graph

Change to: plot(x, -1.2e8*a/25*x + 1.2e8*a) and it should work.

Executing a multiple plot graph

Change to: plot(x, -1.2e8*a/25*x + 1.2e8*a) and it should work.

5 days ago | 0

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Answered

Troubles with Butterworth Bandpass filter

My expertise in this area stops with the filters and thier implementations. An appropriate time vector: Fs = 1000; L = num...

Troubles with Butterworth Bandpass filter

My expertise in this area stops with the filters and thier implementations. An appropriate time vector: Fs = 1000; L = num...

6 days ago | 0