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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

Perform inverse weighted least squares regression

‘Would this be 1/error of each point?’ That would appear to be a reasonable approach, since the data with the smallest errors...

Perform inverse weighted least squares regression

‘Would this be 1/error of each point?’ That would appear to be a reasonable approach, since the data with the smallest errors...

3 hours ago | 0

Answered

Finding the frequency and the phase shift of a Sin signal

One option is described in Curve fitting to a sinusoidal function and a version that could be more appropriate to your problem ...

Finding the frequency and the phase shift of a Sin signal

One option is described in Curve fitting to a sinusoidal function and a version that could be more appropriate to your problem ...

5 hours ago | 1

| accepted

Answered

Find all possible ordered pairs that satisfy a linear equation

The ‘all possible’ criterion would produce infinite solutions. I suspect you would spend the rest of your life calculationg it!...

Find all possible ordered pairs that satisfy a linear equation

The ‘all possible’ criterion would produce infinite solutions. I suspect you would spend the rest of your life calculationg it!...

5 hours ago | 0

Answered

cell2table is not recognizing certain columns (not all) containing double data

I am not certain what the problem is with readcell, however unless it is absolutely necessary to use it, use readtable instead, ...

cell2table is not recognizing certain columns (not all) containing double data

I am not certain what the problem is with readcell, however unless it is absolutely necessary to use it, use readtable instead, ...

8 hours ago | 0

Answered

Simulation of drug distribution with ordinary differential equation

The syntax was not passing the parameters correctly to ‘ode_ex’, and was not passing to correct arguments, at least from what I ...

Simulation of drug distribution with ordinary differential equation

The syntax was not passing the parameters correctly to ‘ode_ex’, and was not passing to correct arguments, at least from what I ...

8 hours ago | 0

Answered

What is a more efficient method of increasing non-zero entries by one

I am not exactly certain what you want to do, however it is straightforward to do this using logical indexing — R = [0, 0, 4, ...

What is a more efficient method of increasing non-zero entries by one

I am not exactly certain what you want to do, however it is straightforward to do this using logical indexing — R = [0, 0, 4, ...

8 hours ago | 0

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Answered

is poctave function working ?

The code you posted runs correctly in R2021a, since it runs correctly in the online Run feature here that uses it — Fs = 44.1E...

is poctave function working ?

The code you posted runs correctly in R2021a, since it runs correctly in the online Run feature here that uses it — Fs = 44.1E...

11 hours ago | 0

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Answered

Undefined operator '*' for input arguments of type 'categorical'.

I am not certain what the problem is, and some information is not available. Try something like this — sample = readtable('...

Undefined operator '*' for input arguments of type 'categorical'.

I am not certain what the problem is, and some information is not available. Try something like this — sample = readtable('...

11 hours ago | 0

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Answered

Export/Copy Plot Line Values

Try siomething like this — x = 0:10; y1 = x.^2; y2 = 50*sin(2*pi*x/10)+50; figure hp = plot(x, y1, x, y2); Line1X = hp...

Export/Copy Plot Line Values

Try siomething like this — x = 0:10; y1 = x.^2; y2 = 50*sin(2*pi*x/10)+50; figure hp = plot(x, y1, x, y2); Line1X = hp...

23 hours ago | 1

| accepted

Answered

Matlab plotting from a data table.

Something like this — T1 = readtable('Your CSVFile.csv'); figure plot(T1{:,1}, T1{:,2}) % Plots Th...

Matlab plotting from a data table.

Something like this — T1 = readtable('Your CSVFile.csv'); figure plot(T1{:,1}, T1{:,2}) % Plots Th...

1 day ago | 0

Answered

Error in multiplying corresponding elements in two matrices

It is often confusing to use ‘l’ (lower-case letter ‘L’) and ‘1’ (number ‘1’). I suspect that is the problem.

Error in multiplying corresponding elements in two matrices

It is often confusing to use ‘l’ (lower-case letter ‘L’) and ‘1’ (number ‘1’). I suspect that is the problem.

1 day ago | 1

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Answered

Find difference between two measurements

Without knowing what the data are, one option would be to use interp1 to determine the same values at specific times. I have ...

Find difference between two measurements

Without knowing what the data are, one option would be to use interp1 to determine the same values at specific times. I have ...

1 day ago | 0

Answered

Solve 3 unknown variable system of equations

There are likely an infinity of solutions. Also, for whatever reason, the solve function does not like ‘L6’. A numeric a...

Solve 3 unknown variable system of equations

There are likely an infinity of solutions. Also, for whatever reason, the solve function does not like ‘L6’. A numeric a...

1 day ago | 0

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Answered

Error using sym>convertChar (line 1537) when solving an ODE using laplace transform. How to fix the problem?

Eliminate the single quotes, use double equal signs in the symbolic expression, express ‘x’ as ‘x(t)’ in the syms declaration (o...

Error using sym>convertChar (line 1537) when solving an ODE using laplace transform. How to fix the problem?

Eliminate the single quotes, use double equal signs in the symbolic expression, express ‘x’ as ‘x(t)’ in the syms declaration (o...

2 days ago | 0

Answered

Curavture/Slope Filtering

One approach could be to look for changes in the slope (using the gradient function here) with respect to the number of elements...

Curavture/Slope Filtering

One approach could be to look for changes in the slope (using the gradient function here) with respect to the number of elements...

2 days ago | 0

Answered

How can I find the heart rate and R-R time interval for ECG Signal?

Getting the information from the file was something of an adventure! I likely could have done this with detectImportOptions, ho...

How can I find the heart rate and R-R time interval for ECG Signal?

Getting the information from the file was something of an adventure! I likely could have done this with detectImportOptions, ho...

2 days ago | 0

| accepted

Answered

Help me with Graph plot

One approach — syms x y = 6*x^3 - 37*x^2 + 37*x - 10 figure fplot(y) grid .

Help me with Graph plot

One approach — syms x y = 6*x^3 - 37*x^2 + 37*x - 10 figure fplot(y) grid .

2 days ago | 0

Answered

Solve the 2-nd order differential equations y"+2y'=3x

One approach would be to do this symbolically and solve it using the dsolve function.

Solve the 2-nd order differential equations y"+2y'=3x

One approach would be to do this symbolically and solve it using the dsolve function.

2 days ago | 0

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Answered

Error with ode45

Supply the ‘t’ argument even if the code does not use it. Try this — t=[0 5]; inity = 1; [t,y]=ode45(@f, t, inity); plot...

Error with ode45

Supply the ‘t’ argument even if the code does not use it. Try this — t=[0 5]; inity = 1; [t,y]=ode45(@f, t, inity); plot...

3 days ago | 0

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Answered

Data import and Header Line

There are several ways to do this, likely the easiest is to use the readmatrix function (introduced in R2019a).

Data import and Header Line

There are several ways to do this, likely the easiest is to use the readmatrix function (introduced in R2019a).

3 days ago | 0

| accepted

Answered

Error while using cellfun with a function

Try this instead — RRTrain1 = cellfun(@(x)RRfeatures(x),XTrain,'UniformOutput',false); I have no idea if that will do what yo...

Error while using cellfun with a function

Try this instead — RRTrain1 = cellfun(@(x)RRfeatures(x),XTrain,'UniformOutput',false); I have no idea if that will do what yo...

3 days ago | 1

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Answered

Strange curve fitting with large polynomial degrees when using polyfit

As a general rule, a polynomial fit with a degree grater than 7 is likely not appropriate, so a 100 degree polynomial is giving ...

Strange curve fitting with large polynomial degrees when using polyfit

As a general rule, a polynomial fit with a degree grater than 7 is likely not appropriate, so a 100 degree polynomial is giving ...

3 days ago | 1

Answered

How to group companies by SIC codes

The discretize function could be appropriate for this.

How to group companies by SIC codes

The discretize function could be appropriate for this.

3 days ago | 0

Answered

3D plot from excel

Try something like this — T1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/616758/Shear%20stress...

3D plot from excel

Try something like this — T1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/616758/Shear%20stress...

3 days ago | 1

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Answered

Adding a single number to an entire matrix

Exactly as you wrote it! a = 5 b = [1,2,3;4,5,6;7,8,9] c = a + b Use square brackets [] to code vectors and matrices.

Adding a single number to an entire matrix

Exactly as you wrote it! a = 5 b = [1,2,3;4,5,6;7,8,9] c = a + b Use square brackets [] to code vectors and matrices.

3 days ago | 0

Answered

Frequency domain and time-frequency domain for sae data

The pspectrum function can likely help with this, specifically with respect to the time-frequency plot.

Frequency domain and time-frequency domain for sae data

The pspectrum function can likely help with this, specifically with respect to the time-frequency plot.

4 days ago | 0

Answered

Help with conditional statement

My approach to these problems is to take advantage of MATLAB’s logical vectors. So for example, if I wanted to construct a fu...

Help with conditional statement

My approach to these problems is to take advantage of MATLAB’s logical vectors. So for example, if I wanted to construct a fu...

4 days ago | 1

Answered

Add constraints to nonlinear multiple data sets fit

The nlinfit function will not allow parameter constraints. Use lsqcurvefit for that instead. Note that it is then possible t...

Add constraints to nonlinear multiple data sets fit

The nlinfit function will not allow parameter constraints. Use lsqcurvefit for that instead. Note that it is then possible t...

4 days ago | 0

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Answered

Use input from an array in a function

The ‘plan’ array is not being passed to your function, and since the function has its own workspace (that it does not share with...

Use input from an array in a function

The ‘plan’ array is not being passed to your function, and since the function has its own workspace (that it does not share with...

4 days ago | 0

| accepted

Answered

Solving state space equation by ode45

The MATLAB ODE solvers are adaptive, and so will solve with as narrow a difference in the time steps as necessary to produce a s...

Solving state space equation by ode45

The MATLAB ODE solvers are adaptive, and so will solve with as narrow a difference in the time steps as necessary to produce a s...

4 days ago | 0