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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

Change value for another value

Consider this example: A = [99999 rand(1,2); rand 99999 rand; rand(1,2) 99999]; B = A; B(A == 99999) = 0 producing: A = ...

Change value for another value

Consider this example: A = [99999 rand(1,2); rand 99999 rand; rand(1,2) 99999]; B = A; B(A == 99999) = 0 producing: A = ...

14 hours ago | 1

Answered

Inter-rater reliability

If I understand what your data are and what you want to do, The correct test for your data is Fleiss’s kappa statistic. As I re...

Inter-rater reliability

If I understand what your data are and what you want to do, The correct test for your data is Fleiss’s kappa statistic. As I re...

15 hours ago | 0

Answered

Edge distortion when resampling a signal

From the documentation: ‘When filtering, resample assumes that the input sequence, x, is zero before and after the samples it ...

Edge distortion when resampling a signal

From the documentation: ‘When filtering, resample assumes that the input sequence, x, is zero before and after the samples it ...

17 hours ago | 0

Answered

3D Plotting in matlab

I assume ‘complex’ just means complicated, and not a function with real an imaginary arguments or output. If it is actually com...

3D Plotting in matlab

I assume ‘complex’ just means complicated, and not a function with real an imaginary arguments or output. If it is actually com...

19 hours ago | 1

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Answered

plotting ode warning with nor plot returned

It helps to look at the dsolve results: Bsol = S.B Asol = S.A that are: Bsol = 0 ...

plotting ode warning with nor plot returned

It helps to look at the dsolve results: Bsol = S.B Asol = S.A that are: Bsol = 0 ...

19 hours ago | 0

Answered

RMSE between original and predicted values.

Please see my Comment replying to your Comment.

RMSE between original and predicted values.

Please see my Comment replying to your Comment.

19 hours ago | 0

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Answered

standard deviation on power vs. frequency graph

It would help to have your data, however I created some to illustrate the approach: f = linspace(0, 0.5, 25); ...

standard deviation on power vs. frequency graph

It would help to have your data, however I created some to illustrate the approach: f = linspace(0, 0.5, 25); ...

20 hours ago | 0

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Answered

How to plot two MATLAB polar plot in a single figure?

The hold calls must go after the appropriate figure call, not before it. Example— a = linspace(0, 2*pi); r1 = abs(cos(a));...

How to plot two MATLAB polar plot in a single figure?

The hold calls must go after the appropriate figure call, not before it. Example— a = linspace(0, 2*pi); r1 = abs(cos(a));...

22 hours ago | 1

Answered

Multiple Linear Regression using fitlm function

In a linear regression of any sort, there is only one intercept.

Multiple Linear Regression using fitlm function

In a linear regression of any sort, there is only one intercept.

22 hours ago | 0

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Answered

How to calculate the derivate of an equation ?

To calculate a numerical derivative of a vector, use the gradient function. If ‘N’ is a vector, use gradient on it, then mult...

How to calculate the derivate of an equation ?

To calculate a numerical derivative of a vector, use the gradient function. If ‘N’ is a vector, use gradient on it, then mult...

22 hours ago | 0

| accepted

Answered

take values from old matrix to newer

Create the output matrix ‘B’ as: B = A(all(A(:,3:5) >= 0, 2),:) % Result Example— A = [randi(9...

take values from old matrix to newer

Create the output matrix ‘B’ as: B = A(all(A(:,3:5) >= 0, 2),:) % Result Example— A = [randi(9...

22 hours ago | 0

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Answered

Matlab gives no result when I use the ODE (Ordinary Differential Equations)

The differential equation is nonlinear (the ‘y^2’ term) and very few nonlinear differential equations have analytic solutions. ...

Matlab gives no result when I use the ODE (Ordinary Differential Equations)

The differential equation is nonlinear (the ‘y^2’ term) and very few nonlinear differential equations have analytic solutions. ...

23 hours ago | 0

Answered

How to filter data that detects peaks or irregularities?

Several functions already exist to do that, among which are findpeaks, islocalmax, ischange, and others.

How to filter data that detects peaks or irregularities?

Several functions already exist to do that, among which are findpeaks, islocalmax, ischange, and others.

1 day ago | 0

Answered

Get an image as an input from webcam

I assume here that you are using a USB webcam, and not the Image Aquisition Toolbox. To take picture, use the snapshot functi...

Get an image as an input from webcam

I assume here that you are using a USB webcam, and not the Image Aquisition Toolbox. To take picture, use the snapshot functi...

1 day ago | 0

Answered

How to get a 3D image from 2D countourf?

Black surf plots are common with very densely-gridded data. To avoid that, set 'EdgeColor' to 'none': D = load('Pedobarograp...

How to get a 3D image from 2D countourf?

Black surf plots are common with very densely-gridded data. To avoid that, set 'EdgeColor' to 'none': D = load('Pedobarograp...

1 day ago | 0

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Answered

Reverse calculate a table of values

I am not certain what a ‘3D table’ is. Perhaps you intend a three column table or array. If that is true, then the interp1 f...

Reverse calculate a table of values

I am not certain what a ‘3D table’ is. Perhaps you intend a three column table or array. If that is true, then the interp1 f...

2 days ago | 1

Answered

Sequence a_n =1/n

Use element-wise division: n = 1:100; format short Seq = 1./n producing: Seq = 1.0000 0.5000 0.3333 0.2500 ...

Sequence a_n =1/n

Use element-wise division: n = 1:100; format short Seq = 1./n producing: Seq = 1.0000 0.5000 0.3333 0.2500 ...

2 days ago | 1

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Answered

Calculate area under curve of multiple peaks

Using cumtrapz: [peaks,loc]=findpeaks(crestbar, 'MinPeakProminence', 30); [trofs,troflocs] = findpeaks(-crestbar, 'MinPeakPro...

Calculate area under curve of multiple peaks

Using cumtrapz: [peaks,loc]=findpeaks(crestbar, 'MinPeakProminence', 30); [trofs,troflocs] = findpeaks(-crestbar, 'MinPeakPro...

2 days ago | 0

Answered

We need to install Global Optimization Tool

Try running these lines from a script or your Command Window first: restoredefaultpath rehash toolboxcache That may fix th...

We need to install Global Optimization Tool

Try running these lines from a script or your Command Window first: restoredefaultpath rehash toolboxcache That may fix th...

2 days ago | 0

Answered

convert plot3 to contour plot

Use the griddata function: a = randi(9, 10, 3); x = a(:,1); y = a(:,2); z = a(:,3); xv = linspace(min(x), max(x), 6); ...

convert plot3 to contour plot

Use the griddata function: a = randi(9, 10, 3); x = a(:,1); y = a(:,2); z = a(:,3); xv = linspace(min(x), max(x), 6); ...

2 days ago | 0

Answered

Index exceeds matrix dimensions error "for my code"

It is unfortunate that we do not get the opportunity to see what ‘X’ is for the various files, nor anything else about them. ...

Index exceeds matrix dimensions error "for my code"

It is unfortunate that we do not get the opportunity to see what ‘X’ is for the various files, nor anything else about them. ...

2 days ago | 0

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Answered

this is a part of my test and i cant find the mistake in this .

The obvious observation is that ‘x’ is going to be less than 10 from the initial iteration through how many iterations it takes ...

this is a part of my test and i cant find the mistake in this .

The obvious observation is that ‘x’ is going to be less than 10 from the initial iteration through how many iterations it takes ...

2 days ago | 0

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Answered

Error in saveas, Invalid figure handle

I cannot run your code because I do not have the necessary files. However: %% Let's plot T and RH times...

Error in saveas, Invalid figure handle

I cannot run your code because I do not have the necessary files. However: %% Let's plot T and RH times...

3 days ago | 0

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Answered

Custom colour bar, excluding the Blue from RGB.

Define ‘CustomColourMap’ as: CustomColourMap = @(x) [linspace(0,1,x).' linspace(1,0,x).' zeros(x,1)]; then to use it: Cust...

Custom colour bar, excluding the Blue from RGB.

Define ‘CustomColourMap’ as: CustomColourMap = @(x) [linspace(0,1,x).' linspace(1,0,x).' zeros(x,1)]; then to use it: Cust...

3 days ago | 0

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Answered

how to make fuction from changing varibles

That is relatively straightforward to do with ndgrid or meshgrid. Try this hypothetical example: Z = @(x,y,z) x.^2 + y.^2 +...

how to make fuction from changing varibles

That is relatively straightforward to do with ndgrid or meshgrid. Try this hypothetical example: Z = @(x,y,z) x.^2 + y.^2 +...

3 days ago | 0

Answered

Add 0.5 *0.5 degree grid on figure (country)

This illustrates the general approach: x = linspace(44, 64); y = linspace(25, 40); t = linspace(0,2*pi); circx = 0.25*(ma...

Add 0.5 *0.5 degree grid on figure (country)

This illustrates the general approach: x = linspace(44, 64); y = linspace(25, 40); t = linspace(0,2*pi); circx = 0.25*(ma...

3 days ago | 0

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Answered

How can i plot with if statement ?

Try this: x=[10 20 30 40 50 ] ; for k = 1:numel(x) if x(k)==10 y(k)=((10*10^6)*.1523)./ x(k) ; end if...

How can i plot with if statement ?

Try this: x=[10 20 30 40 50 ] ; for k = 1:numel(x) if x(k)==10 y(k)=((10*10^6)*.1523)./ x(k) ; end if...

3 days ago | 0

Answered

Make a Plot using loop

Subscript ‘Cp’ and the plot magically appears! Dg=150; %mg Vd=50; %L Ke=0.4; %h^-1 Ka=1.6; %h^-1 t=0:0.1:10; for k = 1...

Make a Plot using loop

Subscript ‘Cp’ and the plot magically appears! Dg=150; %mg Vd=50; %L Ke=0.4; %h^-1 Ka=1.6; %h^-1 t=0:0.1:10; for k = 1...

3 days ago | 0

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Answered

titel for tables with spce between the words

The R2019b release allows spaces and other (inluuding Unicode) characters in table variable names. Upgrade to it and you will b...

titel for tables with spce between the words

The R2019b release allows spaces and other (inluuding Unicode) characters in table variable names. Upgrade to it and you will b...

3 days ago | 1