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Answered

Notch filtering from coefficients

The function gives you the ‘b’ vector for the filter. The ‘a’ vector is 1, since this appears to be a FIR filter design. To ...

Notch filtering from coefficients

The function gives you the ‘b’ vector for the filter. The ‘a’ vector is 1, since this appears to be a FIR filter design. To ...

alrededor de 10 horas ago | 0

Answered

Accessing a value in a vector from a conditional statement

There are several ways to do this. My approach: v=[6 10 25 35 50 65 80]; x=10.02; y=10.47; mv=max(x*.125,y*1.25); ind =...

Accessing a value in a vector from a conditional statement

There are several ways to do this. My approach: v=[6 10 25 35 50 65 80]; x=10.02; y=10.47; mv=max(x*.125,y*1.25); ind =...

alrededor de 11 horas ago | 0

Answered

nlinfit with modelfun as an integral2 and variable integral limits

Part of the problem is that since ‘Integralfun’ is your objective function, it needs to be of the form: fun = @(parameter_vecto...

nlinfit with modelfun as an integral2 and variable integral limits

Part of the problem is that since ‘Integralfun’ is your objective function, it needs to be of the form: fun = @(parameter_vecto...

alrededor de 15 horas ago | 0

Answered

How can I do implicit differentiation

I can find no documentation that it is possible in MATLAB (as much as I like it). See this Wolfram Alpha page for the correct...

How can I do implicit differentiation

I can find no documentation that it is possible in MATLAB (as much as I like it). See this Wolfram Alpha page for the correct...

1 día ago | 0

Answered

run command 100 times and put the answers in one vector

Use a for loop. Assign the appropriate ‘results’ to a cell array (if they are different sizes in each iteration), or vector (if...

run command 100 times and put the answers in one vector

Use a for loop. Assign the appropriate ‘results’ to a cell array (if they are different sizes in each iteration), or vector (if...

1 día ago | 0

Answered

How do I plot different array smoothly which contain NaN in same figure

One option is to use the fillmissing function. Example — sig1 = [rand(1,10) NaN]; sig2 = [rand(1,10) NaN]; sig3 = [rand(1...

How do I plot different array smoothly which contain NaN in same figure

One option is to use the fillmissing function. Example — sig1 = [rand(1,10) NaN]; sig2 = [rand(1,10) NaN]; sig3 = [rand(1...

1 día ago | 0

Answered

numerical solution of a system of ODE which is not in standard form

It would likely help to have your code. If you want more tractable numerical results, use the vpa function. The double funct...

numerical solution of a system of ODE which is not in standard form

It would likely help to have your code. If you want more tractable numerical results, use the vpa function. The double funct...

1 día ago | 1

| accepted

Answered

Play an audio files with different volumes

See my Answer to your duplicate Question.

Play an audio files with different volumes

See my Answer to your duplicate Question.

1 día ago | 0

Answered

Play an audio file with different volume

Use the sound function with the appropriate multiplicaiton factor. (Note, there is no guarantee that the result will not be cli...

Play an audio file with different volume

Use the sound function with the appropriate multiplicaiton factor. (Note, there is no guarantee that the result will not be cli...

1 día ago | 0

Answered

pol2cart with matrices

This appears to be the same as: using surf and pol2cart on matrix. You can get a 2D plot of it by using: view(0,90) Anothe...

pol2cart with matrices

This appears to be the same as: using surf and pol2cart on matrix. You can get a 2D plot of it by using: view(0,90) Anothe...

2 días ago | 0

Answered

Create custom x-axis for 'imagesc' plot

Much of your code is ‘over the horizon’ and so out of sight. Try something like this: x = 0:500; ...

Create custom x-axis for 'imagesc' plot

Much of your code is ‘over the horizon’ and so out of sight. Try something like this: x = 0:500; ...

2 días ago | 0

| accepted

Answered

fitting a circle with fitnlm

The arguments to ‘circlefun’ are reversed. The parameter vector must always be the first argument, and the independent variable...

fitting a circle with fitnlm

The arguments to ‘circlefun’ are reversed. The parameter vector must always be the first argument, and the independent variable...

2 días ago | 1

| accepted

Answered

3D Matrix extraction and manipulation

That can be straightforward or slightly complicated, depending on how you want to do it. To extract the first 67 rows: M = ...

3D Matrix extraction and manipulation

That can be straightforward or slightly complicated, depending on how you want to do it. To extract the first 67 rows: M = ...

3 días ago | 0

| accepted

Answered

Contaminate an EMG with 50 Hz signal

I have no idea what ‘isn’t working’ means. This version of your code works: Fs = 256; ...

Contaminate an EMG with 50 Hz signal

I have no idea what ‘isn’t working’ means. This version of your code works: Fs = 256; ...

3 días ago | 0

| accepted

Answered

How to color individual points on errorbar plot?

You need to plot with respect to an independent variable. Try this: means=[1 1 2 3 4]; standarddeviation=[0.1 0.2 0.2 0.3 ...

How to color individual points on errorbar plot?

You need to plot with respect to an independent variable. Try this: means=[1 1 2 3 4]; standarddeviation=[0.1 0.2 0.2 0.3 ...

3 días ago | 0

Answered

displacing iterations of a signal

I am not certain what you want to do. If you want the different waveforms to appear consecutively, plot them against an indepen...

displacing iterations of a signal

I am not certain what you want to do. If you want the different waveforms to appear consecutively, plot them against an indepen...

3 días ago | 0

Answered

How can I plot shaded confidence intervals on my plot?

Add these two patch calls after the last plot call and before the hold off call: patch([x fliplr(x)], [y-CI fliplr(y+CI)], [0,...

How can I plot shaded confidence intervals on my plot?

Add these two patch calls after the last plot call and before the hold off call: patch([x fliplr(x)], [y-CI fliplr(y+CI)], [0,...

4 días ago | 1

| accepted

Answered

how to obtain the frequency when doing the fourier trasform

Assuming that the data are regularly sampled, so that the sampling intervals are the same for all of them, I usually do somethin...

how to obtain the frequency when doing the fourier trasform

Assuming that the data are regularly sampled, so that the sampling intervals are the same for all of them, I usually do somethin...

4 días ago | 0

| accepted

Answered

Month as a two digit number

To have leading zeros, it has to be a character array or string variable. Try this: Date = datetime('now'); mth = sprintf(...

Month as a two digit number

To have leading zeros, it has to be a character array or string variable. Try this: Date = datetime('now'); mth = sprintf(...

4 días ago | 2

Answered

Designing a fir filter and how to apply it to a signal

You need to normalise the stopband frequencies by the Nyquist frequency. Try this: Wn=[fp1 fp2]/(fs/2); That worked when I...

Designing a fir filter and how to apply it to a signal

You need to normalise the stopband frequencies by the Nyquist frequency. Try this: Wn=[fp1 fp2]/(fs/2); That worked when I...

4 días ago | 0

| accepted

Answered

Energy calculation via current signal integration with limits

Add this after your posted code: idxrng = iVs:iVe; IntP = cumtrapz(T(idxrng), P(idxrng)); figure subplot(3,1,1) yyaxis l...

Energy calculation via current signal integration with limits

Add this after your posted code: idxrng = iVs:iVe; IntP = cumtrapz(T(idxrng), P(idxrng)); figure subplot(3,1,1) yyaxis l...

4 días ago | 0

| accepted

Answered

Contour plot of data on a non-rectangular xy domain

I am not certain what you want. Try this: X = [0.940727422583647 1.07008276356436 1.22692065834036 1.36057673106938 1.47757...

Contour plot of data on a non-rectangular xy domain

I am not certain what you want. Try this: X = [0.940727422583647 1.07008276356436 1.22692065834036 1.36057673106938 1.47757...

4 días ago | 0

| accepted

Answered

Position and extraction of row

It would definitely help to see what ‘mergetable1’ is, and how you are getting ‘AccelSN’. If ‘AccelSN’ is read as a string (f...

Position and extraction of row

It would definitely help to see what ‘mergetable1’ is, and how you are getting ‘AccelSN’. If ‘AccelSN’ is read as a string (f...

5 días ago | 0

| accepted

Answered

signal fourier transform include unit step function

Try this version of your code: syms t x(t) % t = linspace(-20, 20, 5000); % u = @(t) (t >= 0); x(t) = exp(-t) * heaviside...

signal fourier transform include unit step function

Try this version of your code: syms t x(t) % t = linspace(-20, 20, 5000); % u = @(t) (t >= 0); x(t) = exp(-t) * heaviside...

5 días ago | 0

| accepted

Answered

Matlab dsolve function issue with format.

My (R2020a) version requires slightly different symbolic convetions. Try this: syms x(t) Dx = diff(x); D2x = diff(Dx); e...

Matlab dsolve function issue with format.

My (R2020a) version requires slightly different symbolic convetions. Try this: syms x(t) Dx = diff(x); D2x = diff(Dx); e...

5 días ago | 0

| accepted

Answered

Extraplotation of impedance data

First, I doubt that extrapolating from 250 kHz to 10 MHz is appropriate in any event. However it could be, if you identified ...

Extraplotation of impedance data

First, I doubt that extrapolating from 250 kHz to 10 MHz is appropriate in any event. However it could be, if you identified ...

5 días ago | 0

Answered

Why I can't use the function of decimate

I get the same result as in the documentation (in R2020a). First, what version of MATLAB are you using? The current online d...

Why I can't use the function of decimate

I get the same result as in the documentation (in R2020a). First, what version of MATLAB are you using? The current online d...

5 días ago | 0

| accepted

Answered

determine the R waves to evaluate the ECG signal and determine the heart rate.

Use findpeaks or islocalmax to locate the R-wave peaks.

determine the R waves to evaluate the ECG signal and determine the heart rate.

Use findpeaks or islocalmax to locate the R-wave peaks.

5 días ago | 0

| accepted

Answered

Rolve function around axis to create 3D surface.

See: Plotting an exponential exp(-x), in 3D? for an example.

Rolve function around axis to create 3D surface.

See: Plotting an exponential exp(-x), in 3D? for an example.

6 días ago | 1

| accepted

Answered

Error using ss. How do i fix this?

Transpose ‘BS’ to a column vector (everywhere you use it, since you re-define it): BS=[0 0 0 0 0 0 k4/m4 0].'; Do the same f...

Error using ss. How do i fix this?

Transpose ‘BS’ to a column vector (everywhere you use it, since you re-define it): BS=[0 0 0 0 0 0 k4/m4 0].'; Do the same f...

6 días ago | 1

| accepted