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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

Please, How do I determine the Mean Absolute Value (MAV) of an acoustic signal, which has positive and negative data points?

The mean value is the ‘average’ value. In almost all audio signals, the mean value is either 0 or close to 0. An electrocar...

Please, How do I determine the Mean Absolute Value (MAV) of an acoustic signal, which has positive and negative data points?

The mean value is the ‘average’ value. In almost all audio signals, the mean value is either 0 or close to 0. An electrocar...

circa 9 ore ago | 0

Answered

xlswrite is not recommended, what should I use instead?

Since you have R2020a, first, create a table using your data, then use writetable to write it to an Excel file (or other options...

xlswrite is not recommended, what should I use instead?

Since you have R2020a, first, create a table using your data, then use writetable to write it to an Excel file (or other options...

1 giorno ago | 1

Answered

Hello everyone, how to divide a piece of data into upper and lower parts along the y-axis with C point and D point as the boundary?

Try this: D = load('data1.mat'); data1 = D.data1; x = data1(:, 1); y = data1(:, 2); [C,ixmin] = min(x); [D,ixmax] = max...

Hello everyone, how to divide a piece of data into upper and lower parts along the y-axis with C point and D point as the boundary?

Try this: D = load('data1.mat'); data1 = D.data1; x = data1(:, 1); y = data1(:, 2); [C,ixmin] = min(x); [D,ixmax] = max...

1 giorno ago | 1

| accepted

Answered

Hodgkin-Huxley Error Code: Index exceeds the number of array elements (1)

Your differential equation returns a column vector of 4 elements, so it is necessary for the initial conditions vector and whate...

Hodgkin-Huxley Error Code: Index exceeds the number of array elements (1)

Your differential equation returns a column vector of 4 elements, so it is necessary for the initial conditions vector and whate...

1 giorno ago | 0

Answered

contourf plot gives white bands

Without your data, it is not possible to determine with any certainty what the problem is. Two observations: First, [X,...

contourf plot gives white bands

Without your data, it is not possible to determine with any certainty what the problem is. Two observations: First, [X,...

1 giorno ago | 0

Answered

Value of x for which AUC reaches a given value

‘I calculate the AUC using the trapz function.’ That being the problem. Use cumtrapz instead: t = linspace(0, 1, 500); ...

Value of x for which AUC reaches a given value

‘I calculate the AUC using the trapz function.’ That being the problem. Use cumtrapz instead: t = linspace(0, 1, 500); ...

1 giorno ago | 1

| accepted

Answered

How can I solve this equation in which variable is in power

One option is to use GlobalSearch: y = [2.1544; 1.71; 1.99; 1.59]; rhs = @(a,b,c,d) [a*(5.95.^b) + c.*(5.95.^d); a.*(6.72.^b)...

How can I solve this equation in which variable is in power

One option is to use GlobalSearch: y = [2.1544; 1.71; 1.99; 1.59]; rhs = @(a,b,c,d) [a*(5.95.^b) + c.*(5.95.^d); a.*(6.72.^b)...

1 giorno ago | 1

| accepted

Answered

running MATLAB ode45 back-to-back

‘The first state solution that is returned, is it the same as the initial condition?’ In my experience, yes. Sometimes it is...

running MATLAB ode45 back-to-back

‘The first state solution that is returned, is it the same as the initial condition?’ In my experience, yes. Sometimes it is...

2 giorni ago | 1

| accepted

Answered

How to flip the data upside down without flipping the axes?

I am not certain what result you want. Try this: x = [1 2 3]; y = [6 13 11]; figure plot(x,max(y)-y+min(y)) .

How to flip the data upside down without flipping the axes?

I am not certain what result you want. Try this: x = [1 2 3]; y = [6 13 11]; figure plot(x,max(y)-y+min(y)) .

2 giorni ago | 0

| accepted

Answered

Plot contour with 3 variables

The contour function requires matrices. You will need to create the matrices from your vectors. Try this (with your actual d...

Plot contour with 3 variables

The contour function requires matrices. You will need to create the matrices from your vectors. Try this (with your actual d...

2 giorni ago | 1

| accepted

Answered

how to apply bandpass filter to a .wav file

Use the bandpass function. For best results, also specify: 'ImpulseResponse','iir'

how to apply bandpass filter to a .wav file

Use the bandpass function. For best results, also specify: 'ImpulseResponse','iir'

2 giorni ago | 0

Answered

How to adjust data?

It would be easiest to use the detrend function: t = linspace(0, 100, 1E+4); % Create Data s = sin(2*...

How to adjust data?

It would be easiest to use the detrend function: t = linspace(0, 100, 1E+4); % Create Data s = sin(2*...

3 giorni ago | 0

Answered

how to set axis with different interval ?

One option is to change the scale of the x-axis: % x y M = [ 3 10 5 11 7 09 10 12...

how to set axis with different interval ?

One option is to change the scale of the x-axis: % x y M = [ 3 10 5 11 7 09 10 12...

3 giorni ago | 0

| accepted

Answered

How to find period of a signal using fft?

Prototype fft code: t = ...; % Time Vector s = ...; ...

How to find period of a signal using fft?

Prototype fft code: t = ...; % Time Vector s = ...; ...

3 giorni ago | 0

| accepted

Answered

Record best solution in each GA generation running with UseParallel=true

See: How to save data from Genetic Algorithm in case MATLAB crashes? That will likely do what you want. Define it as the out...

Record best solution in each GA generation running with UseParallel=true

See: How to save data from Genetic Algorithm in case MATLAB crashes? That will likely do what you want. Define it as the out...

3 giorni ago | 0

Answered

Fitting experimental data to spring damper ODE

You have already referenced two (of the many possibilities I have posted) to estimate the parameters of your system that I would...

Fitting experimental data to spring damper ODE

You have already referenced two (of the many possibilities I have posted) to estimate the parameters of your system that I would...

3 giorni ago | 0

Answered

How do I find the indices of NaN values in a cell array?

Try this: D = load('XTrain2_all.mat'); XTrain2_all = D.XTrain2_all; hasNaN = cellfun(@nnz,cellfun(@isnan, XTrain2_all, 'Un...

How do I find the indices of NaN values in a cell array?

Try this: D = load('XTrain2_all.mat'); XTrain2_all = D.XTrain2_all; hasNaN = cellfun(@nnz,cellfun(@isnan, XTrain2_all, 'Un...

4 giorni ago | 0

Answered

sum in sequence, string, matrix

Try this: M = 1:8760; % Create Vector Mr = reshape(M, 24, []); % Reshape V...

sum in sequence, string, matrix

Try this: M = 1:8760; % Create Vector Mr = reshape(M, 24, []); % Reshape V...

4 giorni ago | 1

| accepted

Answered

How to implement a FIR approximation of the analytic signal

I am not certain what you want to do or what the problem is with the hilbert function. If you have calculated the spectrum (u...

How to implement a FIR approximation of the analytic signal

I am not certain what you want to do or what the problem is with the hilbert function. If you have calculated the spectrum (u...

4 giorni ago | 0

| accepted

Answered

MATLAB stem function error

Either just use ‘z1’, or use a ‘shape’ argument with conv: n = -15:15; u = n>=0; u1 = n>= 4; f = u-u1; z1 = conv(f,f,'same...

MATLAB stem function error

Either just use ‘z1’, or use a ‘shape’ argument with conv: n = -15:15; u = n>=0; u1 = n>= 4; f = u-u1; z1 = conv(f,f,'same...

4 giorni ago | 0

Answered

Draw shapes not in a graph

Try something like this: x1 = rand(1,5); y1 = rand(1,5); x2 = rand(1,7); y2 = rand(1,7); figure plot(x1, y1, 'or', 'Mar...

Draw shapes not in a graph

Try something like this: x1 = rand(1,5); y1 = rand(1,5); x2 = rand(1,7); y2 = rand(1,7); figure plot(x1, y1, 'or', 'Mar...

4 giorni ago | 0

Answered

please help me (dsolve)

The single quotation marks are likely the problem. Try this slightly edited version: syms y(t) Dy = diff(y); D2y = diff(...

please help me (dsolve)

The single quotation marks are likely the problem. Try this slightly edited version: syms y(t) Dy = diff(y); D2y = diff(...

4 giorni ago | 0

Answered

How Do I Fitting a 3 Unknown Parameter Model?

There are several functions available to estimate the parameters. This uses fminsearch because everyone has it: VFTfcn = @(b,...

How Do I Fitting a 3 Unknown Parameter Model?

There are several functions available to estimate the parameters. This uses fminsearch because everyone has it: VFTfcn = @(b,...

5 giorni ago | 0

| accepted

Answered

Matlab interpolation between two surfaces

Experiment with this: x = linspace(-5, 5, 20); y = x; [X,Y] = ndgrid(x,y); z = @(x,y,s,h,a) a .* exp(s*(x.^2+y.^2)) + h; ...

Matlab interpolation between two surfaces

Experiment with this: x = linspace(-5, 5, 20); y = x; [X,Y] = ndgrid(x,y); z = @(x,y,s,h,a) a .* exp(s*(x.^2+y.^2)) + h; ...

5 giorni ago | 0

Answered

complementary error function (surf plot)

Add: [X,T] = ndgrid(x,t); and it works: x = linspace(0,10^(-6),20); t = linspace(0,5,5); [X,T] = ndgrid(x,t); u0 = 10^(-...

complementary error function (surf plot)

Add: [X,T] = ndgrid(x,t); and it works: x = linspace(0,10^(-6),20); t = linspace(0,5,5); [X,T] = ndgrid(x,t); u0 = 10^(-...

5 giorni ago | 0

| accepted

Answered

Solving equations using Laplace transform

Unless you are solving a partial differential equation, such that the Laplace transform produces an ordinary differential equati...

Solving equations using Laplace transform

Unless you are solving a partial differential equation, such that the Laplace transform produces an ordinary differential equati...

6 giorni ago | 0

| accepted

Answered

Answers editor seems to be broken

The website was updated. I had the same problem, and it turned out that Rena’s suggestion that clearing the Firefox cache solve...

Answers editor seems to be broken

The website was updated. I had the same problem, and it turned out that Rena’s suggestion that clearing the Firefox cache solve...

6 giorni ago | 0

| accepted

Answered

Error using atan2 Inputs must be real.

If you want to compute the phase angle of a complex number, use the angle function.

Error using atan2 Inputs must be real.

If you want to compute the phase angle of a complex number, use the angle function.

6 giorni ago | 0

| accepted

Answered

How to get unknown number of variables to be all same length through interpolation

Try this approach: V1 = sort(rand(1,5)); % Original Vector V2 = sort(rand(1,10)...

How to get unknown number of variables to be all same length through interpolation

Try this approach: V1 = sort(rand(1,5)); % Original Vector V2 = sort(rand(1,10)...

6 giorni ago | 0

Answered

ode15s error（Genetic algorithm for differential equation parameter identification）

I cannot follow your code. See Ode system solution with unknown constant for one example of an approach that generally works....

ode15s error（Genetic algorithm for differential equation parameter identification）

I cannot follow your code. See Ode system solution with unknown constant for one example of an approach that generally works....

6 giorni ago | 0