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Answered

pplane update for Matlab 2020b?

The R2020b release is likely a few weeks off. Otherwise, one option is: dfield and pplane (Java versions) and others are avai...

pplane update for Matlab 2020b?

The R2020b release is likely a few weeks off. Otherwise, one option is: dfield and pplane (Java versions) and others are avai...

circa 16 ore ago | 0

Answered

Change numerical data points to dates

Neither MATLAB nor I understand ‘0120’ in what otherwise appears to be the year field in the date vector. Try this: datstr ...

Change numerical data points to dates

Neither MATLAB nor I understand ‘0120’ in what otherwise appears to be the year field in the date vector. Try this: datstr ...

circa 20 ore ago | 0

Answered

Nonlinear least-squares data fit

The objective function needs to be coded as: ffcn = @(c) f(c,x) - y; with the complete lsqnonlin call being: f=@(c,x) c(1)...

Nonlinear least-squares data fit

The objective function needs to be coded as: ffcn = @(c) f(c,x) - y; with the complete lsqnonlin call being: f=@(c,x) c(1)...

circa 21 ore ago | 0

| accepted

Answered

Problem with FFT amplitude plot

To see the frequency peaks, it is necessary first to remove the D-C offset by subtyracting the mean of the signal: D1 = readma...

Problem with FFT amplitude plot

To see the frequency peaks, it is necessary first to remove the D-C offset by subtyracting the mean of the signal: D1 = readma...

1 giorno ago | 1

Answered

parameter estimation with lsqcurvefit and boundary value ode (BVP4c)

The lsqcurvefit function needs to have the output of the objective function the same size (with respect to row and column dimens...

parameter estimation with lsqcurvefit and boundary value ode (BVP4c)

The lsqcurvefit function needs to have the output of the objective function the same size (with respect to row and column dimens...

1 giorno ago | 1

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Answered

Reading Text Files with Numbers and String

Try this: fidi = fopen('data1.txt'); A = textscan(fidi, 'ID#: %f time: %f A: %f B: %f C %f', 'Delimiter',{'\t',';'}, 'Multipl...

Reading Text Files with Numbers and String

Try this: fidi = fopen('data1.txt'); A = textscan(fidi, 'ID#: %f time: %f A: %f B: %f C %f', 'Delimiter',{'\t',';'}, 'Multipl...

2 giorni ago | 1

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Answered

How to make a loop that performs the same operation on a large matrix ?

I am not certain what you intend by ‘groups of three rows’, or how you would like them calcculalted Try this: M = randn(64,...

How to make a loop that performs the same operation on a large matrix ?

I am not certain what you intend by ‘groups of three rows’, or how you would like them calcculalted Try this: M = randn(64,...

2 giorni ago | 1

Answered

Removing first half signal

If ‘signal’ is the signal vector and ‘t’ is the time vector: new_t = t(ceil(numel(signal)/2):end); new_signal = signal(ceil(n...

Removing first half signal

If ‘signal’ is the signal vector and ‘t’ is the time vector: new_t = t(ceil(numel(signal)/2):end); new_signal = signal(ceil(n...

2 giorni ago | 1

| accepted

Answered

Surface plot by using three vectors of the same length

The surf plot only requires that ‘Z’ is a matrix. The ‘X’ and ‘Y’ arguments are good to have, although not necessary (and they ...

Surface plot by using three vectors of the same length

The surf plot only requires that ‘Z’ is a matrix. The ‘X’ and ‘Y’ arguments are good to have, although not necessary (and they ...

2 giorni ago | 1

| accepted

Answered

Logarithmic scale with a different base

Try this: N = 1:10000; M = 61; L = N-M+1; ova_complex = ((N.*(log2(N)+1))./(N-M+1)); figure stem(log2(N),ova_complex) x...

Logarithmic scale with a different base

Try this: N = 1:10000; M = 61; L = N-M+1; ova_complex = ((N.*(log2(N)+1))./(N-M+1)); figure stem(log2(N),ova_complex) x...

2 giorni ago | 0

Answered

Frequency response of a parallel IIR filter

If they were in series, the transfer functions would be multiplied, and in parallel, added, according to Series and Parallel Tra...

Frequency response of a parallel IIR filter

If they were in series, the transfer functions would be multiplied, and in parallel, added, according to Series and Parallel Tra...

2 giorni ago | 0

| accepted

Answered

Text position based on another Text

I am not certain what the problem is. Try something like this: x = 1:20; y = 10*sin(pi*x/5); figure plot(x, y) grid ...

Text position based on another Text

I am not certain what the problem is. Try something like this: x = 1:20; y = 10*sin(pi*x/5); figure plot(x, y) grid ...

3 giorni ago | 0

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Answered

Select rows based on a string in a cell

Use strcmpi (the case-insensitive version of the function) instead.

Select rows based on a string in a cell

Use strcmpi (the case-insensitive version of the function) instead.

3 giorni ago | 1

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Answered

Operands to the || and && operators must be convertible to logical scalar values.

EDIT — (12 Aug 2020 at 20:30) I suspect that ‘locs’ is a column vector, and that is causing the problems both with the loop (be...

Operands to the || and && operators must be convertible to logical scalar values.

EDIT — (12 Aug 2020 at 20:30) I suspect that ‘locs’ is a column vector, and that is causing the problems both with the loop (be...

3 giorni ago | 0

Answered

how to compute the complex Fourier series expansion of half-wave rectified signal. and plot its phase and amplitude spectrum?

My impression is that this is homework. We give hints for homework, not complete code. (You must write the code. We will help...

how to compute the complex Fourier series expansion of half-wave rectified signal. and plot its phase and amplitude spectrum?

My impression is that this is homework. We give hints for homework, not complete code. (You must write the code. We will help...

3 giorni ago | 1

Answered

Spectral Entropy vs Frequency

Plotting spectral entropy as a function of frequency is actually described in the documentation in: Plot Spectral Entropy of Spe...

Spectral Entropy vs Frequency

Plotting spectral entropy as a function of frequency is actually described in the documentation in: Plot Spectral Entropy of Spe...

3 giorni ago | 0

Answered

x-intersection of part of extended line from curve

Add these lines to your code after the ‘m’ calculation and before figure(1): B = [TC ones(size(TC))] \ IC; ...

x-intersection of part of extended line from curve

Add these lines to your code after the ‘m’ calculation and before figure(1): B = [TC ones(size(TC))] \ IC; ...

3 giorni ago | 0

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Answered

i kind want to pull the blue curve forward in time to match the red curve , so that the peaks match in time. that is the marker curve should be moved 20 seconds forward.

Just add (or subtract) 20 seconds from the blue curve time value, then plot them together. A simple example: xr = 1:20; yr...

i kind want to pull the blue curve forward in time to match the red curve , so that the peaks match in time. that is the marker curve should be moved 20 seconds forward.

Just add (or subtract) 20 seconds from the blue curve time value, then plot them together. A simple example: xr = 1:20; yr...

3 giorni ago | 0

Answered

Find slope signal change

The ischange function (introduced in R2017b) is helpful here.

Find slope signal change

The ischange function (introduced in R2017b) is helpful here.

3 giorni ago | 0

Answered

How to plot confident interval of ecdf() as shade?

Try this: a = rand(30,1); [f1,x1,up,low] = ecdf(a); idx = ~isnan(up) & ~isnan(low); figure plot(x1(idx), f1(idx), '-r') ...

How to plot confident interval of ecdf() as shade?

Try this: a = rand(30,1); [f1,x1,up,low] = ecdf(a); idx = ~isnan(up) & ~isnan(low); figure plot(x1(idx), f1(idx), '-r') ...

3 giorni ago | 1

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Answered

PROBLEM USING PLOT AND SUBPLOT WITH HANDLE FUNCTION

Since ‘q’ is a function, it must be evaluated as a function. Try this: P=@(N) (L*V)./q(N); then: subplot(2,3,1) plot(P(...

PROBLEM USING PLOT AND SUBPLOT WITH HANDLE FUNCTION

Since ‘q’ is a function, it must be evaluated as a function. Try this: P=@(N) (L*V)./q(N); then: subplot(2,3,1) plot(P(...

4 giorni ago | 0

Answered

atan2(0,0) is not undefined (NaN)

That is defined in the IEEE Compliance section of the atan2 documentation. The result also isd not completely standardised. ...

atan2(0,0) is not undefined (NaN)

That is defined in the IEEE Compliance section of the atan2 documentation. The result also isd not completely standardised. ...

4 giorni ago | 1

| accepted

Answered

How to plot duration where time rolls over days?

You will need to convert these to your duration array, however the day-of-year conversion (using DDD in the InputFormat string) ...

How to plot duration where time rolls over days?

You will need to convert these to your duration array, however the day-of-year conversion (using DDD in the InputFormat string) ...

4 giorni ago | 0

Answered

How to loop time ( hours and minutes ) in a data set

The retime function (and the timetable creation that is necessary to use it) is likely the best option.

How to loop time ( hours and minutes ) in a data set

The retime function (and the timetable creation that is necessary to use it) is likely the best option.

5 giorni ago | 0

Answered

Smoothing curve with duplicate values using pchip

The unique call should result in no duplicate values in ‘xUnique’. I do not have access to your data, however instead of being ...

Smoothing curve with duplicate values using pchip

The unique call should result in no duplicate values in ‘xUnique’. I do not have access to your data, however instead of being ...

5 giorni ago | 0

Answered

How To Create A Persistence Plot

Perhaps something like this: x = linspace(0, 10, 250); %...

How To Create A Persistence Plot

Perhaps something like this: x = linspace(0, 10, 250); %...

5 giorni ago | 1

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Answered

plotting error bars in both x and y data

I am not certain what the problem is. See: Control Error Bars Lengths in All Directions .

plotting error bars in both x and y data

I am not certain what the problem is. See: Control Error Bars Lengths in All Directions .

5 giorni ago | 0

| accepted

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...

5 giorni ago | 1

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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...

5 giorni 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...

6 giorni ago | 0