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Answered

saying that Index in position 2 exceeds array bounds (must not exceed 1) for line 7

There are two problems that I can see. First, ‘data_2’ is a column vector, so it does not have a second column, and ‘x’ must ...

saying that Index in position 2 exceeds array bounds (must not exceed 1) for line 7

There are two problems that I can see. First, ‘data_2’ is a column vector, so it does not have a second column, and ‘x’ must ...

3 hours ago | 0

Answered

Gradient of a 2D plot

See the gradient documentation section on Contour Plot of Vector Field . It demonstrates exactly what you are describing.

Gradient of a 2D plot

See the gradient documentation section on Contour Plot of Vector Field . It demonstrates exactly what you are describing.

5 hours ago | 0

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Answered

I wrote some function and I knew it is correct in matematics but I cann´t get eny output. Can you please help me?

I cannot run your function because I have no idea what the arguments should be. Hiowever one problem is obvious. One of the ...

I wrote some function and I knew it is correct in matematics but I cann´t get eny output. Can you please help me?

I cannot run your function because I have no idea what the arguments should be. Hiowever one problem is obvious. One of the ...

7 hours ago | 0

Answered

Save the measurement data

As a general (or first) approach the save function would likely be appropriate. I have no idea what the data actually are or wh...

Save the measurement data

As a general (or first) approach the save function would likely be appropriate. I have no idea what the data actually are or wh...

7 hours ago | 0

Answered

Fitting an ODE set with time dependent parameters to data

You could certainly estimate it by integrating it with ode45, however it has an analytic solution (kindly provided by the Symbol...

Fitting an ODE set with time dependent parameters to data

You could certainly estimate it by integrating it with ode45, however it has an analytic solution (kindly provided by the Symbol...

7 hours ago | 0

Answered

Error using fprintf Unable to convert 'sym' value to 'double'.

If you have R2016b or later, use vpaintegral: This works (with the fprintf call corrected to eliminate the spaces between the ...

Error using fprintf Unable to convert 'sym' value to 'double'.

If you have R2016b or later, use vpaintegral: This works (with the fprintf call corrected to eliminate the spaces between the ...

20 hours ago | 0

Answered

how i plot this function

One way, using the exact equation you posted: syms x t a = 4.2; % Use Appropriate Val...

how i plot this function

One way, using the exact equation you posted: syms x t a = 4.2; % Use Appropriate Val...

21 hours ago | 1

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Answered

Error using sin Not enough input arguments

You have it partially correct. Try this: y4 = sin(t) .* sin(t); If you want to multiply thge second one by ‘t’ do this: ...

Error using sin Not enough input arguments

You have it partially correct. Try this: y4 = sin(t) .* sin(t); If you want to multiply thge second one by ‘t’ do this: ...

22 hours ago | 0

Answered

Missing days in Time Table when calculating means

It appears to be correct when I look at at it, with complete day series and zeros in the second column, apparently for the missi...

Missing days in Time Table when calculating means

It appears to be correct when I look at at it, with complete day series and zeros in the second column, apparently for the missi...

22 hours ago | 0

Answered

How Calculate R squared from a linear regress

They are hidden in the ‘stats’ output: [b,~,~,~,stats] = regress(y(:),[ones(size(x(:))),x(:)]); % get the intercept and slope ...

How Calculate R squared from a linear regress

They are hidden in the ‘stats’ output: [b,~,~,~,stats] = regress(y(:),[ones(size(x(:))),x(:)]); % get the intercept and slope ...

1 day ago | 0

Answered

How to solve the Gompertz Equation

The reason the red line does not plot is that ‘b’ goes from about 3 to about 32, however ‘E’ is constant at about 451.7. So ‘E’...

How to solve the Gompertz Equation

The reason the red line does not plot is that ‘b’ goes from about 3 to about 32, however ‘E’ is constant at about 451.7. So ‘E’...

2 days ago | 0

Answered

Why am I getting "Array indices must be positive or integers values"?

Rhe reason is that ‘up(t)’ was being interpreted as an indexing operation rather than a function call, and ‘t’ are not all posit...

Why am I getting "Array indices must be positive or integers values"?

Rhe reason is that ‘up(t)’ was being interpreted as an indexing operation rather than a function call, and ‘t’ are not all posit...

2 days ago | 0

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Answered

plotting with for loop

To plot all of them on the same axes, put the figure call before the loop instead of inside it: figure hold on for i=1:lengt...

plotting with for loop

To plot all of them on the same axes, put the figure call before the loop instead of inside it: figure hold on for i=1:lengt...

2 days ago | 0

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Answered

system of ordinary differential equations

Note that it will be necessary to use ODE Event Location to stop and then re-start the integration at the discontinuities (, ) s...

system of ordinary differential equations

Note that it will be necessary to use ODE Event Location to stop and then re-start the integration at the discontinuities (, ) s...

2 days ago | 0

Answered

Plotting Intersection point on plot

Try this: Cpo = -0.75;a = 3.32; M = 0.2:0.01:0.8; Cp = Cpo./sqrt(1-M.^2); Cp_cr = 2./(a*M.^2) .* ((((2+(a-1)*M.^2)/(a+1))...

Plotting Intersection point on plot

Try this: Cpo = -0.75;a = 3.32; M = 0.2:0.01:0.8; Cp = Cpo./sqrt(1-M.^2); Cp_cr = 2./(a*M.^2) .* ((((2+(a-1)*M.^2)/(a+1))...

3 days ago | 1

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Answered

Getting an error for quiver 3

MATLAB uses U.S. English spelling conventions. See the Quiver Properties documentation section on Color .

Getting an error for quiver 3

MATLAB uses U.S. English spelling conventions. See the Quiver Properties documentation section on Color .

3 days ago | 1

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Answered

How to do Z transform with Z^-1 format?

The only option I can think of has nothing to do with the Symbolic Math Toolbox, and is instead the Variable argument in the Con...

How to do Z transform with Z^-1 format?

The only option I can think of has nothing to do with the Symbolic Math Toolbox, and is instead the Variable argument in the Con...

3 days ago | 1

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Answered

Find absolute, relative, and mean power of theta, beta and TBR (theta/beta ratio)

You can filter them using the approach in Need to break down EEG signals into 4 frequency bands. Once you have the filtered s...

Find absolute, relative, and mean power of theta, beta and TBR (theta/beta ratio)

You can filter them using the approach in Need to break down EEG signals into 4 frequency bands. Once you have the filtered s...

3 days ago | 0

Answered

Why are my staitistic functions returning an array rather than a single value?

The min, max, and mean functions operate on the first dimension that is greater than 1, so for a matrix, they will all produce a...

Why are my staitistic functions returning an array rather than a single value?

The min, max, and mean functions operate on the first dimension that is greater than 1, so for a matrix, they will all produce a...

3 days ago | 0

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Answered

Curve classification with interference/disturbance

One option is to evaluate the exponential curve at exactly the same values of the independent variable as the data (that I assum...

Curve classification with interference/disturbance

One option is to evaluate the exponential curve at exactly the same values of the independent variable as the data (that I assum...

3 days ago | 0

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Answered

Hello, I am having trouble plotting this graph. Whenever I run my code I get an error that I am not using the plot function correctly or I get a blank graph. I think it may have to do with how I solved my equation for T. Thanks for any help.

You are using the wrong plot function. Use fplot instead: fplot(Teq,[0 1]) xlabel('t') ylabel('Teq') EDIT — (27 Sep 20...

Hello, I am having trouble plotting this graph. Whenever I run my code I get an error that I am not using the plot function correctly or I get a blank graph. I think it may have to do with how I solved my equation for T. Thanks for any help.

You are using the wrong plot function. Use fplot instead: fplot(Teq,[0 1]) xlabel('t') ylabel('Teq') EDIT — (27 Sep 20...

3 days ago | 0

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Answered

Generate name of the given plot as output

I have absolutely no idea what you are asking. See if title or figure will do what you want.

Generate name of the given plot as output

I have absolutely no idea what you are asking. See if title or figure will do what you want.

3 days ago | 0

Answered

Need help to run this code

To use a function handle in a calculation, it is necessary to evaluate the function so it will be replaced by the numeric output...

Need help to run this code

To use a function handle in a calculation, it is necessary to evaluate the function so it will be replaced by the numeric output...

3 days ago | 0

Answered

Matlab code for fractions

Use the rat function: x = 1.5 [num,den] = rat(x) producing: num = 3 den = 2 .

Matlab code for fractions

Use the rat function: x = 1.5 [num,den] = rat(x) producing: num = 3 den = 2 .

3 days ago | 0

Answered

How to plot with 3 matrix

If you want the red and green lines to show, you need to plot them separately, and create handles for them to pass to the legend...

How to plot with 3 matrix

If you want the red and green lines to show, you need to plot them separately, and create handles for them to pass to the legend...

3 days ago | 1

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Answered

Error using plot Not enough input arguments.

You may need to use the cell2mat function, or concatenate the elements inside a vector, using this (strange-looking but effectiv...

Error using plot Not enough input arguments.

You may need to use the cell2mat function, or concatenate the elements inside a vector, using this (strange-looking but effectiv...

3 days ago | 0

Answered

Getting FWHM from distribution fitter

One way to get the FWHM is to use the findpeaks function. It may be ‘overkill’ for only one peak, however it should give you th...

Getting FWHM from distribution fitter

One way to get the FWHM is to use the findpeaks function. It may be ‘overkill’ for only one peak, however it should give you th...

4 days ago | 0

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Answered

Trying to use findpeaks to isolate the portion of the signal that has a positive slope

This will identify and plot the positive slopes: T1 = readtable('73(4)_interval.xlsx'); Slope = gradient(T1{:,1}) ./ gradient...

Trying to use findpeaks to isolate the portion of the signal that has a positive slope

This will identify and plot the positive slopes: T1 = readtable('73(4)_interval.xlsx'); Slope = gradient(T1{:,1}) ./ gradient...

4 days ago | 0

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Answered

Using text, 2 variables, and decimals in fprintf

Try this: fprintf("The value you entered %.1f°C\nis equal to %.1f°F\n", temp, ans) so: temp = 10; ans = 50; fprintf("The ...

Using text, 2 variables, and decimals in fprintf

Try this: fprintf("The value you entered %.1f°C\nis equal to %.1f°F\n", temp, ans) so: temp = 10; ans = 50; fprintf("The ...

4 days ago | 0

| accepted