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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

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(...

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(...

1 hour 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....

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....

2 hours ago | 0

Answered

Suggestions for financial simulation

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

Suggestions for financial simulation

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

3 hours ago | 0

Answered

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.

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.

3 hours ago | 0

Answered

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...

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...

13 hours 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...

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...

14 hours 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...

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...

15 hours 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 ...

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 ...

18 hours 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)...

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)...

21 hours 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...

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...

22 hours ago | 1

| accepted

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...

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...

22 hours ago | 0

Answered

How to represent continuous time Transfer function in a script

(1.) Correct! (2.) No.

How to represent continuous time Transfer function in a script

(1.) Correct! (2.) No.

1 day 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...

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...

1 day ago | 0

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Answered

How do I specify a variable from a table that uses words and not numerical values

One approach: C = {'NA'; 'NA'; 'NA'; 'NA'; 'something else'; 'NA'; 'orange peel'; 'NA'; 'NA'; 'NA'}; T1 = cell2table(C); ...

How do I specify a variable from a table that uses words and not numerical values

One approach: C = {'NA'; 'NA'; 'NA'; 'NA'; 'something else'; 'NA'; 'orange peel'; 'NA'; 'NA'; 'NA'}; T1 = cell2table(C); ...

1 day ago | 0

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...

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...

1 day 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...

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...

1 day 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...

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 days ago | 0

Answered

how to normalize EKG/ ECG signal

See if the rescale function (introduced in R2017b) will do what you want.

how to normalize EKG/ ECG signal

See if the rescale function (introduced in R2017b) will do what you want.

2 days 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: ...

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 days ago | 0

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; ...

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 days ago | 0

Answered

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...

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 days 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 ...

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 days 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...

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 days ago | 1

| accepted

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...

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 days 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...

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 days 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:...

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 days ago | 0

Answered

Trying to solve a differential equation

Add ‘Fmag’ to the syms declaration to get — .

Trying to solve a differential equation

Add ‘Fmag’ to the syms declaration to get — .

3 days ago | 0

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Answered

Interpolating between end points in polar coordinates

Try this: polcords = [13.7807 208.5120 13.9924 225.4886 19.3740 232.1227 14.2353 26...

Interpolating between end points in polar coordinates

Try this: polcords = [13.7807 208.5120 13.9924 225.4886 19.3740 232.1227 14.2353 26...

3 days ago | 1

Answered

Transfer function fit estimate

I’m not certain exactly what you’re plotting. I always use the compare function to see how closely the estimated system matches...

Transfer function fit estimate

I’m not certain exactly what you’re plotting. I always use the compare function to see how closely the estimated system matches...

3 days ago | 0

Answered

To define the frequency range when we use FFT

First, change ‘t’ to: t=linspace(0, 300, 600); % Needs To Be Regularly-Spaced then for a t...

To define the frequency range when we use FFT

First, change ‘t’ to: t=linspace(0, 300, 600); % Needs To Be Regularly-Spaced then for a t...

3 days ago | 0

| accepted