12,591 total contributions since 2012

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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

naming your rows and column for a matrix

Use array2table to put your matrix in a table (R2013b and later). Name the columns with Specify Variable Names, and the rows w...

naming your rows and column for a matrix

Use array2table to put your matrix in a table (R2013b and later). Name the columns with Specify Variable Names, and the rows w...

3 hours ago | 1

Answered

Defining the limits for discrete time sequence on x axis using stem command

Add these lines to each subplot: xt = get(gca, 'XTick'); set(gca, 'XTick',min(xt):max(xt)) so the revised code is now: x=[...

Defining the limits for discrete time sequence on x axis using stem command

Add these lines to each subplot: xt = get(gca, 'XTick'); set(gca, 'XTick',min(xt):max(xt)) so the revised code is now: x=[...

5 hours ago | 0

| accepted

Answered

How to locate a decimal in a matrix?

It depends on what you want. If you want the indices, use both. If you want the values, just rem (or mod) will work. Try th...

How to locate a decimal in a matrix?

It depends on what you want. If you want the indices, use both. If you want the values, just rem (or mod) will work. Try th...

8 hours ago | 1

| accepted

Answered

The most efficient way to locate the first 1's in each row of a matrix

The max function will return the indices of the first instances of the maximum value it encounters, in the desired dimension. S...

The most efficient way to locate the first 1's in each row of a matrix

The max function will return the indices of the first instances of the maximum value it encounters, in the desired dimension. S...

9 hours ago | 1

Answered

Ploting problems with handle, maybe I have changes in this function.

Although I usually suggest that images of code are inappropriate, that might be a way to figure out what is wrong with this line...

Ploting problems with handle, maybe I have changes in this function.

Although I usually suggest that images of code are inappropriate, that might be a way to figure out what is wrong with this line...

9 hours ago | 0

Answered

Need help implementing a 2D circular gaussian

If you want to plot a surface, you need to use matrix arguments. Try this: x = linspace(-3, 3); y = x; [X,Y] = ndgrid(x,y...

Need help implementing a 2D circular gaussian

If you want to plot a surface, you need to use matrix arguments. Try this: x = linspace(-3, 3); y = x; [X,Y] = ndgrid(x,y...

14 hours ago | 1

| accepted

Answered

exp(A) gives zero in the first argument

Try this: format longE exp([71 307]) producing: ans = 6.837671229762744e+30 2.130129192828224e+133 See the docu...

exp(A) gives zero in the first argument

Try this: format longE exp([71 307]) producing: ans = 6.837671229762744e+30 2.130129192828224e+133 See the docu...

15 hours ago | 0

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Answered

how to plot a continuous signal

This should get you started: u = @(t) t>=0; x = @(t,u) cos(200*pi*t.*u(t)); t = linspace(-1, 1); figure(1) plot(t, x(t,u))...

how to plot a continuous signal

This should get you started: u = @(t) t>=0; x = @(t,u) cos(200*pi*t.*u(t)); t = linspace(-1, 1); figure(1) plot(t, x(t,u))...

15 hours ago | 0

| accepted

Answered

How to change the color of a plane

How would you define ‘Z0’ as a matrix the size of ‘X’ (or ‘‘Y’) that is uniformly zero? (We only give hints to homework probl...

How to change the color of a plane

How would you define ‘Z0’ as a matrix the size of ‘X’ (or ‘‘Y’) that is uniformly zero? (We only give hints to homework probl...

16 hours ago | 0

Answered

how to find slope for certain area in graph.

To limit ‘angle’ (and ‘force’) to calculate the slope only on the ‘angle’ limits between 2 and 14, try this: Lv = (angle >= 2)...

how to find slope for certain area in graph.

To limit ‘angle’ (and ‘force’) to calculate the slope only on the ‘angle’ limits between 2 and 14, try this: Lv = (angle >= 2)...

16 hours ago | 0

| accepted

Answered

Problem with function legend

Setting: opengl software appears to work for this problem. Also consider: Use Software OpenGL for Future Sessions. See th...

Problem with function legend

Setting: opengl software appears to work for this problem. Also consider: Use Software OpenGL for Future Sessions. See th...

17 hours ago | 0

Answered

how to eliminate undesidered lines

Use the sort or sortrows function to sort your data by the independent variable values.

how to eliminate undesidered lines

Use the sort or sortrows function to sort your data by the independent variable values.

18 hours ago | 0

Answered

Designing a Notch Filter

See: Remove the 60 Hz Hum from a Signal EDIT — (19 Oct 2019 at 3:55) Or, if you want to do it without the filter design ...

Designing a Notch Filter

See: Remove the 60 Hz Hum from a Signal EDIT — (19 Oct 2019 at 3:55) Or, if you want to do it without the filter design ...

1 day ago | 0

Answered

How can I plot a filled cylinder with a specific height?

You can use the cylinder function, however writing your own code is more fun: x = [1 3]; y = [2 5]; r=1; hgt = [2 3]; th=0...

How can I plot a filled cylinder with a specific height?

You can use the cylinder function, however writing your own code is more fun: x = [1 3]; y = [2 5]; r=1; hgt = [2 3]; th=0...

1 day ago | 0

Answered

Problem with my code?

I do not see that you defined ‘Qfresh’ anywhere in your function.

Problem with my code?

I do not see that you defined ‘Qfresh’ anywhere in your function.

1 day ago | 0

Answered

Curve fitting by Genetic Algorithm

I can fit part of your data, however not all of it, because there is some noise in elements 19 through 24 that your function is ...

Curve fitting by Genetic Algorithm

I can fit part of your data, however not all of it, because there is some noise in elements 19 through 24 that your function is ...

1 day ago | 1

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Answered

lsqcurvefit fitting not good

Choose different values for ‘x0’. I used these: x0 = [-2.6; 17; 0.7; 7; 0.0001; -0.7; 0.7]; to get this result: x = -...

lsqcurvefit fitting not good

Choose different values for ‘x0’. I used these: x0 = [-2.6; 17; 0.7; 7; 0.0001; -0.7; 0.7]; to get this result: x = -...

2 days ago | 1

| accepted

Answered

The @ symbol in Matlab

The ‘@’ denotes a function handle. See: What Is a Function Handle? for an extended discussion. In this instance, ‘f’ is ...

The @ symbol in Matlab

The ‘@’ denotes a function handle. See: What Is a Function Handle? for an extended discussion. In this instance, ‘f’ is ...

3 days ago | 0

Answered

How can I plot a X where my dataset crosses the X axis (y=0), but only when dy/dx > 0?

To detect the zero-crossings, the code in Easy way of finding zero crossing of a function , and you can interpolate to get the e...

How can I plot a X where my dataset crosses the X axis (y=0), but only when dy/dx > 0?

To detect the zero-crossings, the code in Easy way of finding zero crossing of a function , and you can interpolate to get the e...

3 days ago | 0

Answered

Matrix dimensions must agree.

Note that you used element-wise division some times when you divided by ‘(2*L)’ but not other times: ue = 1-2.*cos((3.*pi.*x)....

Matrix dimensions must agree.

Note that you used element-wise division some times when you divided by ‘(2*L)’ but not other times: ue = 1-2.*cos((3.*pi.*x)....

3 days ago | 0

Answered

Find intersection of 2 normal distribution

The ‘val’ value is the x-value of the intersection, however you need to start fzero in the correct region for it to return the c...

Find intersection of 2 normal distribution

The ‘val’ value is the x-value of the intersection, however you need to start fzero in the correct region for it to return the c...

3 days ago | 2

| accepted

Answered

solving similtanous equations in loop

One approach: x = [1,2,3,4,5,6,7]; y = [1,2,3,4,5,6,7]; [X,Y] = meshgrid(x,y); xv = X(:); yv = Y(:); % -3*w*sin(x)+ 5*q...

solving similtanous equations in loop

One approach: x = [1,2,3,4,5,6,7]; y = [1,2,3,4,5,6,7]; [X,Y] = meshgrid(x,y); xv = X(:); yv = Y(:); % -3*w*sin(x)+ 5*q...

3 days ago | 0

Answered

Low Pass filter not working

Your stopband attenuation is likely not sufficient to produce any difference. Try this instead: Rs = 60; ...

Low Pass filter not working

Your stopband attenuation is likely not sufficient to produce any difference. Try this instead: Rs = 60; ...

3 days ago | 0

Answered

Plotting bacterial growth using odes

I believe Monod kinetics and curve fitting can help. You are not fitting data, so just use the ODE and ode45 call syntax. ...

Plotting bacterial growth using odes

I believe Monod kinetics and curve fitting can help. You are not fitting data, so just use the ODE and ode45 call syntax. ...

4 days ago | 0

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Answered

What is the best non-linear least square fitting method that will parameter error in addition to parameters?

If you have the Statistics and Machine Learning Toolbox, see if the fitnlm function will do what you want. Other options are nl...

What is the best non-linear least square fitting method that will parameter error in addition to parameters?

If you have the Statistics and Machine Learning Toolbox, see if the fitnlm function will do what you want. Other options are nl...

4 days ago | 0

| accepted

Answered

How does Matlab divide two row vectors by each other to get a scalar?

To expand slightly on that, ‘C’ is the least-squares estimate of the slope of with the y-intercept forced through the origin: ...

How does Matlab divide two row vectors by each other to get a scalar?

To expand slightly on that, ‘C’ is the least-squares estimate of the slope of with the y-intercept forced through the origin: ...

4 days ago | 0

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Answered

How can I get the equation of CDF curve in matlab figure?

The cdfplot function plots an empirical distribution based on the characteristics of your data. You can see if it corresponds t...

How can I get the equation of CDF curve in matlab figure?

The cdfplot function plots an empirical distribution based on the characteristics of your data. You can see if it corresponds t...

4 days ago | 0

Answered

Bandwidth analysis of a system with multidimensional input

The length of the input vector is likely irrelevant, and is not even an argument to the bandwidth function. Note however that t...

Bandwidth analysis of a system with multidimensional input

The length of the input vector is likely irrelevant, and is not even an argument to the bandwidth function. Note however that t...

4 days ago | 1

| accepted

Answered

Get t co-ordinate based off y co-ordinate

Try these: t = 0 * pi:0.119:4 * pi; a = 57; phase_angle = 0.26; y = a*sin((67*pi*t) + phase_angle); y_ofst = y-40; zci ...

Get t co-ordinate based off y co-ordinate

Try these: t = 0 * pi:0.119:4 * pi; a = 57; phase_angle = 0.26; y = a*sin((67*pi*t) + phase_angle); y_ofst = y-40; zci ...

4 days ago | 0

Answered

Unique ID Min and Max with multiple values per Unique ID

One approach: M = [10 10 17 17 17 201 1000; 0.1 69 1.7 33 55 67 0.99].'; [UM1, ia,ic] = unique(M(:,1), 'stable'); Vmx = acc...

Unique ID Min and Max with multiple values per Unique ID

One approach: M = [10 10 17 17 17 201 1000; 0.1 69 1.7 33 55 67 0.99].'; [UM1, ia,ic] = unique(M(:,1), 'stable'); Vmx = acc...

5 days ago | 0