12 890 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

Mldivide gives rank deficency when solving for large full system

See if the lsqr function will do what you want. Another option is to use pinv to do the matrix inversion (not normally an app...

Mldivide gives rank deficency when solving for large full system

See if the lsqr function will do what you want. Another option is to use pinv to do the matrix inversion (not normally an app...

environ 2 heures ago | 0

Answered

i am not able to import excel sheet

One approach would be to open Excel, then save your spreadsheet as a .txt file (likely a comma-delimited text file). Then impor...

i am not able to import excel sheet

One approach would be to open Excel, then save your spreadsheet as a .txt file (likely a comma-delimited text file). Then impor...

environ 2 heures ago | 0

Answered

diff makes M less than what i want by 1 elment and i want to have second derivaitve numircal

Use the gradient function. Specifically: k = 0:0.1:5; figure(4) E=(k.^2)*(1.0540^2)/(2*1000*9.1); fx=gradient(E)./grad...

diff makes M less than what i want by 1 elment and i want to have second derivaitve numircal

Use the gradient function. Specifically: k = 0:0.1:5; figure(4) E=(k.^2)*(1.0540^2)/(2*1000*9.1); fx=gradient(E)./grad...

environ 3 heures ago | 0

Answered

Hello, how to solve this equation E*I*k^4-m*v^2*k^2+2*m*v*w*k+(m+M)w^2=0 numerically where w is variable,

Supply all the scalar parameters, then: Eqn = @(w) E*I*k^2-m*v^2*k^2+2*m*v*w*k+(m+M)w^2; w0 = 42; [w,fval] = fsolve(Eqn, ...

Hello, how to solve this equation E*I*k^4-m*v^2*k^2+2*m*v*w*k+(m+M)w^2=0 numerically where w is variable,

Supply all the scalar parameters, then: Eqn = @(w) E*I*k^2-m*v^2*k^2+2*m*v*w*k+(m+M)w^2; w0 = 42; [w,fval] = fsolve(Eqn, ...

environ 3 heures ago | 0

Answered

Plot ODE Bond Price Model

Not enough information, so I created the missing variables: tv = linspace(0, 100, 25); % Time...

Plot ODE Bond Price Model

Not enough information, so I created the missing variables: tv = linspace(0, 100, 25); % Time...

environ 14 heures ago | 0

Answered

Simple system of ODES with starting condition

The only (relative) mistake I can see is that it is not good to use global variables. Pass the values as extra parameters inste...

Simple system of ODES with starting condition

The only (relative) mistake I can see is that it is not good to use global variables. Pass the values as extra parameters inste...

environ 17 heures ago | 0

Answered

Struggling with iterative matrix multiplication

A loop is necessary. Assuming ‘lamda’, ‘omega’ and ‘phi’ are scalar constants already defined, I would do something like this...

Struggling with iterative matrix multiplication

A loop is necessary. Assuming ‘lamda’, ‘omega’ and ‘phi’ are scalar constants already defined, I would do something like this...

environ 18 heures ago | 1

Answered

HOW TO FİND PEAKS OF FFT

I recognise my code! The second plot call is almost correct. Try this: [pks, locs]=findpeaks(x(Iv)); plot(Fv(locs), p...

HOW TO FİND PEAKS OF FFT

I recognise my code! The second plot call is almost correct. Try this: [pks, locs]=findpeaks(x(Iv)); plot(Fv(locs), p...

environ 21 heures ago | 0

| accepted

Answered

Testing a created function

First, it is best not to use ‘ans’ as a variable, since it is the default variable and can be overwritten. Second, the the if...

Testing a created function

First, it is best not to use ‘ans’ as a variable, since it is the default variable and can be overwritten. Second, the the if...

1 jour ago | 0

| accepted

Answered

Solve a system of linear equations in matrix form

The problem is that the system is sparse, so you need to use sparse functions with it. Try this: Left = [1 -1 0 0 0; 1 0 0 ...

Solve a system of linear equations in matrix form

The problem is that the system is sparse, so you need to use sparse functions with it. Try this: Left = [1 -1 0 0 0; 1 0 0 ...

1 jour ago | 0

| accepted

Answered

Error plotting bode diagram of a transfer function inside a matrix

That is not the error. The error is that you are using the Symbolic Math Toolbox when you need to be using the Control System...

Error plotting bode diagram of a transfer function inside a matrix

That is not the error. The error is that you are using the Symbolic Math Toolbox when you need to be using the Control System...

1 jour ago | 0

| accepted

Answered

how to plot 2D Vector field of a 3D ode

The easiest way is to just change the view direction: figure q=quiver3(x1,y1,z1,u,v,w ,2); figure(gcf); view(0, 90) Make ap...

how to plot 2D Vector field of a 3D ode

The easiest way is to just change the view direction: figure q=quiver3(x1,y1,z1,u,v,w ,2); figure(gcf); view(0, 90) Make ap...

2 jours ago | 0

Answered

Plot doesn't show anything

Try this slight edit of your code: orbit=zeros(1,300); j=0; % parameter range rv=2.8:0.001:4; for k = 1:numel(rv) r =...

Plot doesn't show anything

Try this slight edit of your code: orbit=zeros(1,300); j=0; % parameter range rv=2.8:0.001:4; for k = 1:numel(rv) r =...

2 jours ago | 0

| accepted

Answered

Scatter plot legend marker size is huge

The only possibility I can suggest is to use Yair Altman’s export_fig to export them to PDF.

Scatter plot legend marker size is huge

The only possibility I can suggest is to use Yair Altman’s export_fig to export them to PDF.

2 jours ago | 0

Answered

3D plotting base surface

I am not certain what you are asking. The plot appears to be by the stem3 function. Try this: x = randn(1, 10); y = ran...

3D plotting base surface

I am not certain what you are asking. The plot appears to be by the stem3 function. Try this: x = randn(1, 10); y = ran...

2 jours ago | 0

Answered

Solve Integral Equation with function handles

Every multiplication in ‘Fermi’ needs to be vectorised (with element-wise operations), the Symbolic Math Toolbox is not necessar...

Solve Integral Equation with function handles

Every multiplication in ‘Fermi’ needs to be vectorised (with element-wise operations), the Symbolic Math Toolbox is not necessar...

2 jours ago | 1

| accepted

Answered

Graphs of mean and standard deviation

There are several ways, depending on what you want to do. See the errorbar function for one option.

Graphs of mean and standard deviation

There are several ways, depending on what you want to do. See the errorbar function for one option.

2 jours ago | 0

Answered

scatter with custom color of point

I am not certain what you want. Try this: x = rand(1, 20); y = rand(1, 20); c = y >= 0.5; ...

scatter with custom color of point

I am not certain what you want. Try this: x = rand(1, 20); y = rand(1, 20); c = y >= 0.5; ...

2 jours ago | 0

Answered

Fitting Data to a Non-Linear Curve

One possibility: x=[0 1 2 3 4 5 6 7 8 9 10]; y=[.0242 0.1940 0.2792 0.2358 0.1386 0.0598 0.0238 0.0090 0.0034 0.0013 0.002]; ...

Fitting Data to a Non-Linear Curve

One possibility: x=[0 1 2 3 4 5 6 7 8 9 10]; y=[.0242 0.1940 0.2792 0.2358 0.1386 0.0598 0.0238 0.0090 0.0034 0.0013 0.002]; ...

3 jours ago | 0

Answered

mono font not show up in matlab’s fonts

See: How can I add a new font to the list of available fonts in MATLAB?q - MATLAB Answers - MATLAB Central

mono font not show up in matlab’s fonts

See: How can I add a new font to the list of available fonts in MATLAB?q - MATLAB Answers - MATLAB Central

3 jours ago | 0

Answered

How to use a timer most efficently for finding pings/second

One option for recording the times would be to use the clock function. Then use the etime function to recover the elapsed times...

How to use a timer most efficently for finding pings/second

One option for recording the times would be to use the clock function. Then use the etime function to recover the elapsed times...

3 jours ago | 0

| accepted

Answered

Subplots squished to top of page, manually setting position not working

The code tells subplot to plot 12 rows and 3 columns. Try this instead: ax(ii) = subplot(nplts/3, 3, ii); The result is mu...

Subplots squished to top of page, manually setting position not working

The code tells subplot to plot 12 rows and 3 columns. Try this instead: ax(ii) = subplot(nplts/3, 3, ii); The result is mu...

3 jours ago | 0

| accepted

Answered

Filing/interpolation of irregular sample time series multivariate data

Try this: T1 = readtable('Edward Bam Eddata.txt'); T2 = table2timetable(T1, 'RowTimes','TimeStamp'); T3 = retime(T2, 'daily'...

Filing/interpolation of irregular sample time series multivariate data

Try this: T1 = readtable('Edward Bam Eddata.txt'); T2 = table2timetable(T1, 'RowTimes','TimeStamp'); T3 = retime(T2, 'daily'...

3 jours ago | 0

| accepted

Answered

Need to plot the determinant of the matrix for t 0 to 1?

Try this: PHI = @(t) [ 1, t, t/3-(2*exp(-3*t))/9+2/9, (2*t)/3+(2*exp(-3*t))/9-2/9; 0, 1, (5*exp(-3*t))/12-(3*exp(t))/4+1/...

Need to plot the determinant of the matrix for t 0 to 1?

Try this: PHI = @(t) [ 1, t, t/3-(2*exp(-3*t))/9+2/9, (2*t)/3+(2*exp(-3*t))/9-2/9; 0, 1, (5*exp(-3*t))/12-(3*exp(t))/4+1/...

3 jours ago | 0

| accepted

Answered

MatLab Confidence interval range

Use the tinv function to calculate the critical values for normally-distributed data with varying sample sizes. (This is in the...

MatLab Confidence interval range

Use the tinv function to calculate the critical values for normally-distributed data with varying sample sizes. (This is in the...

3 jours ago | 0

Answered

How can I insert the value of a symbol in symbolic matrix and convert it into a numerical matrix?

Please see Plotting error: Need to plot the evolution of symbolic matrix? to convert it to a numerical matrix (as an anonymous ...

How can I insert the value of a symbol in symbolic matrix and convert it into a numerical matrix?

Please see Plotting error: Need to plot the evolution of symbolic matrix? to convert it to a numerical matrix (as an anonymous ...

3 jours ago | 0

Answered

for loop not working

We o not have your entire code. Note that the transpose call is not necessary, since the mean funciton also accepts a dimension...

for loop not working

We o not have your entire code. Note that the transpose call is not necessary, since the mean funciton also accepts a dimension...

3 jours ago | 0

| accepted

Answered

Plotting error: Need to plot the evolution of symbolic matrix?

Try this: PHI = @(t) [ 1, t, t/3-(2*exp(-3*t))/9+2/9, (2*t)/3+(2*exp(-3*t))/9-2/9; 0, 1, (5*exp(-3*t))/12-(3*exp(t))/4+1/...

Plotting error: Need to plot the evolution of symbolic matrix?

Try this: PHI = @(t) [ 1, t, t/3-(2*exp(-3*t))/9+2/9, (2*t)/3+(2*exp(-3*t))/9-2/9; 0, 1, (5*exp(-3*t))/12-(3*exp(t))/4+1/...

3 jours ago | 0

| accepted

Answered

surface fixed point value Z

I do not have the function you used to create the surface in your Question. Try this with it: [X,Y] = ndgrid(-2.5:0.1:2.5);...

surface fixed point value Z

I do not have the function you used to create the surface in your Question. Try this with it: [X,Y] = ndgrid(-2.5:0.1:2.5);...

4 jours ago | 0

| accepted

Answered

X Y grids on 2D surface plot

If you want to see the grid lines, do not use shading interp Just do: [X,Y,Z] = peaks(25); figure surf(X, Y, Z) grid on ...

X Y grids on 2D surface plot

If you want to see the grid lines, do not use shading interp Just do: [X,Y,Z] = peaks(25); figure surf(X, Y, Z) grid on ...

4 jours ago | 0

| accepted