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Answered

Calculate the date difference

The vectors must have the same sizes. Use between: DaysDiff = between(StartDate(1:numel(EndDate)),EndDate) to get: DaysD...

Calculate the date difference

The vectors must have the same sizes. Use between: DaysDiff = between(StartDate(1:numel(EndDate)),EndDate) to get: DaysD...

alrededor de 4 horas ago | 1

| accepted

Answered

How to use ezplot

The ezsurf (and fsurf) functions accept only single-variable functions. Try this: figure ezcontour(@(x,y) x^2 - 9*y^2 - 81...

How to use ezplot

The ezsurf (and fsurf) functions accept only single-variable functions. Try this: figure ezcontour(@(x,y) x^2 - 9*y^2 - 81...

alrededor de 12 horas ago | 0

Answered

How can I find the successive fluctuations of the ECG data.

See: Identifying QRS point in ECG signal among several others.

How can I find the successive fluctuations of the ECG data.

See: Identifying QRS point in ECG signal among several others.

alrededor de 23 horas ago | 0

Answered

MATLAB Equivalent of Linregress in Python?

If you have the Statisitcs and Machine Learning Toolbox, there are several options, among which are regress and fitlm. There ma...

MATLAB Equivalent of Linregress in Python?

If you have the Statisitcs and Machine Learning Toolbox, there are several options, among which are regress and fitlm. There ma...

1 día ago | 0

Answered

Interpolate, fit, and space data

I have no idea exactly what you want to do, or what your data actually are. For the ‘x’ data, I would probably use the linspa...

Interpolate, fit, and space data

I have no idea exactly what you want to do, or what your data actually are. For the ‘x’ data, I would probably use the linspa...

1 día ago | 0

Answered

Shading an area between two intervals on a plot

It is likely not possible to use area for this, since that is not how it was designed to be used. It is possible to use patch...

Shading an area between two intervals on a plot

It is likely not possible to use area for this, since that is not how it was designed to be used. It is possible to use patch...

1 día ago | 0

| accepted

Answered

Solution of natural frequency equation with fzero function

The fzero function is likelly not appropriate here. I would instead use fsolve, and convert the obsolete inline call to an anon...

Solution of natural frequency equation with fzero function

The fzero function is likelly not appropriate here. I would instead use fsolve, and convert the obsolete inline call to an anon...

2 días ago | 0

Answered

a problem with power spectrum calculation (FFT)

The mean of ‘data’ is -16657.4418730469. This is the D-C component, so it appears at 0 Hz, and completely prevents the details ...

a problem with power spectrum calculation (FFT)

The mean of ‘data’ is -16657.4418730469. This is the D-C component, so it appears at 0 Hz, and completely prevents the details ...

2 días ago | 0

| accepted

Answered

Comapring Values in one Matrix to another

Another approach: A = [373 383 393 403 413 420 451 485 499]; B = [373 453 457 461 464]; C = ones(numel(B),1)*A; ...

Comapring Values in one Matrix to another

Another approach: A = [373 383 393 403 413 420 451 485 499]; B = [373 453 457 461 464]; C = ones(numel(B),1)*A; ...

2 días ago | 0

Answered

How to mark the maximum points in mesh

Add this loop just before the mesh call: for k = 1:size(Response_amp,1) [Ramax(k),Idx(k)] = max(Response_amp(k,:)); ...

How to mark the maximum points in mesh

Add this loop just before the mesh call: for k = 1:size(Response_amp,1) [Ramax(k),Idx(k)] = max(Response_amp(k,:)); ...

2 días ago | 0

Answered

plot curve in matlab

syms qa h = (611375/279 - ((192500000*cos(qa))/93 + ((60000*cos(qa))/31 - 611375/93)^2/9 - 14656250/31)/(2*((153125000000*cos(...

plot curve in matlab

syms qa h = (611375/279 - ((192500000*cos(qa))/93 + ((60000*cos(qa))/31 - 611375/93)^2/9 - 14656250/31)/(2*((153125000000*cos(...

2 días ago | 0

Answered

I need to find the angle from horizontal that tangents to a curve make for multiple points

I am not certain what you want to do, or the result you want. The easiest way to calculate numerical derivatives is to use th...

I need to find the angle from horizontal that tangents to a curve make for multiple points

I am not certain what you want to do, or the result you want. The easiest way to calculate numerical derivatives is to use th...

3 días ago | 1

| accepted

Answered

Interpolation to find harmonics from fft

Consider increasing the frequency resolution by using a longer fft. That may make it easier to detect the harmonics where you e...

Interpolation to find harmonics from fft

Consider increasing the frequency resolution by using a longer fft. That may make it easier to detect the harmonics where you e...

3 días ago | 0

Answered

Reading Files and plotting in matlab

I am not certain what the responses to the input calls should be, so I did not run your code, only looked at it. It appears ...

Reading Files and plotting in matlab

I am not certain what the responses to the input calls should be, so I did not run your code, only looked at it. It appears ...

3 días ago | 0

| accepted

Answered

system of nonlinear equation

That is not going to woork with fsolve for a number of reasons. It is necessary to convert ‘f’ to a numeric (not symbolic) fu...

system of nonlinear equation

That is not going to woork with fsolve for a number of reasons. It is necessary to convert ‘f’ to a numeric (not symbolic) fu...

3 días ago | 0

Answered

Variables under the same name in different .mat files

Use load to load each of the files into a different structure. See Load List of Variables into Structure Array. You can then...

Variables under the same name in different .mat files

Use load to load each of the files into a different structure. See Load List of Variables into Structure Array. You can then...

3 días ago | 0

Answered

Looking for documentation explaining M.' and other symbols to select data from an array

‘M. means the same as M(:,:)‘ No, not ‘M.’. The extra dot will throw an error. I am not certain what you are asking. S...

Looking for documentation explaining M.' and other symbols to select data from an array

‘M. means the same as M(:,:)‘ No, not ‘M.’. The extra dot will throw an error. I am not certain what you are asking. S...

3 días ago | 0

Answered

Creating a vector of datetimes with increments of 15 minutes

Try this: Timestamp = (datetime('2020-06-30 23:45:00') : -minutes(15) : datetime('2015-01-01 00:00:00')).'; Timestamp.Format ...

Creating a vector of datetimes with increments of 15 minutes

Try this: Timestamp = (datetime('2020-06-30 23:45:00') : -minutes(15) : datetime('2015-01-01 00:00:00')).'; Timestamp.Format ...

4 días ago | 0

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Answered

simple question of creating a time vector

Without the exact details of your file (that I suspect is not exactly 60 seconds long), something like this will work: t = lin...

simple question of creating a time vector

Without the exact details of your file (that I suspect is not exactly 60 seconds long), something like this will work: t = lin...

4 días ago | 0

| accepted

Answered

different sound file times

If you want all of the sound files to have the same sampling frequency, use the Signal Processing Toolbox resample function. On...

different sound file times

If you want all of the sound files to have the same sampling frequency, use the Signal Processing Toolbox resample function. On...

4 días ago | 0

Answered

There is something wrong in R.

The problem is in the way you call the exp function. This works: R = ((2.*h).*(f.^3))./((c.^2).*(exp(h.*f/(k.*T))-1)); .

There is something wrong in R.

The problem is in the way you call the exp function. This works: R = ((2.*h).*(f.^3))./((c.^2).*(exp(h.*f/(k.*T))-1)); .

4 días ago | 1

| accepted

Answered

Plot AREA limit in matlab

If you want the area between ‘abb_per’ and 100 filled, use the patch function. Try this: figure patch([n fliplr(n)],[abb_p...

Plot AREA limit in matlab

If you want the area between ‘abb_per’ and 100 filled, use the patch function. Try this: figure patch([n fliplr(n)],[abb_p...

4 días ago | 0

| accepted

Answered

lowpass() not working

A low passband with a very high sampling frequency is asking a lot of any filter. I am somewhat surprised that lowpass used a F...

lowpass() not working

A low passband with a very high sampling frequency is asking a lot of any filter. I am somewhat surprised that lowpass used a F...

4 días ago | 0

Answered

How to plot 3D surface with vector-input function?

The function you coded: FUN = @(x) = x(1).^2+x(2).^2; will only take the first 2 elements of ‘x’ (whatever it is), and will r...

How to plot 3D surface with vector-input function?

The function you coded: FUN = @(x) = x(1).^2+x(2).^2; will only take the first 2 elements of ‘x’ (whatever it is), and will r...

5 días ago | 0

| accepted

Answered

piecewise for use in anonymous functions

One option: Rt0 = @(theta,theta1,theta2,B,H,L1) ((0<=theta) & (theta<theta1)).*(B./2+L1)./cos(theta) + ((theta1<=theta) & (the...

piecewise for use in anonymous functions

One option: Rt0 = @(theta,theta1,theta2,B,H,L1) ((0<=theta) & (theta<theta1)).*(B./2+L1)./cos(theta) + ((theta1<=theta) & (the...

5 días ago | 1

Answered

extract mth and m+1st largest element from a vector

‘Is using sort is the best way?’ Yes.

extract mth and m+1st largest element from a vector

‘Is using sort is the best way?’ Yes.

5 días ago | 0

Answered

How to write a multi line string?

Since ‘tran_models’ is an array, just use a loop: for k = 1:size(tran_models,1) fprintf(File,'%s\n', tran_models(k,:)); ...

How to write a multi line string?

Since ‘tran_models’ is an array, just use a loop: for k = 1:size(tran_models,1) fprintf(File,'%s\n', tran_models(k,:)); ...

5 días ago | 0

| accepted

Answered

How can I plot and reach to this figure ?

birthday = datenum(year, month, day); t = 0:ceil(datenum(now)-birthday); Physical = sin(2*pi*t/23); The rest would be calcula...

How can I plot and reach to this figure ?

birthday = datenum(year, month, day); t = 0:ceil(datenum(now)-birthday); Physical = sin(2*pi*t/23); The rest would be calcula...

5 días ago | 0

Answered

Solving the Kinetic equations by Matlab coding

Try this: % % % k(1) = R_Inf, k(2) = k R1fcn = @(k,t) k(1).*(1-exp(-k(2).*t)); R2fcn = @(k,t) k(1).*(1 - (1-exp(-k(2).*t))...

Solving the Kinetic equations by Matlab coding

Try this: % % % k(1) = R_Inf, k(2) = k R1fcn = @(k,t) k(1).*(1-exp(-k(2).*t)); R2fcn = @(k,t) k(1).*(1 - (1-exp(-k(2).*t))...

5 días ago | 0

Answered

Changing scientific notation to long format

Select an appropriate option (such as long g) with the format function.

Changing scientific notation to long format

Select an appropriate option (such as long g) with the format function.

5 días ago | 0

| accepted