12.915 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

Plotting a line given its slope and one coordinate

Try this: x = 88; y = 56; slope = 1.08; y_intercept = y - slope*x; xv = [0 100]; figure plot(xv, slope*xv+y_intercep...

Plotting a line given its slope and one coordinate

Try this: x = 88; y = 56; slope = 1.08; y_intercept = y - slope*x; xv = [0 100]; figure plot(xv, slope*xv+y_intercep...

etwa 2 Stunden ago | 0

Answered

Need help displaying an output file for data.

I have no idea what you want to do. However if you create a table of your results, writetable could do what you want.

Need help displaying an output file for data.

I have no idea what you want to do. However if you create a table of your results, writetable could do what you want.

etwa 3 Stunden ago | 1

| accepted

Answered

Error Message Using ODE45

The code you posted runs for me without error: function dydt = vdp1(t,y) %VDP1 Evaluate the van der Pol ODEs for mu = 1 % ...

Error Message Using ODE45

The code you posted runs for me without error: function dydt = vdp1(t,y) %VDP1 Evaluate the van der Pol ODEs for mu = 1 % ...

etwa 4 Stunden ago | 0

Answered

Repeat 3-D array elements

Use the repmat function: A = rand(67, 960, 80); B = repmat(A, 1, 1, 3); sizeB = size(B) producing: sizeB = 67 960 ...

Repeat 3-D array elements

Use the repmat function: A = rand(67, 960, 80); B = repmat(A, 1, 1, 3); sizeB = size(B) producing: sizeB = 67 960 ...

etwa 9 Stunden ago | 0

Answered

AREA UNDER the CURVE

Defining your matrix as ‘M’, use the trapz function twice, once in each dimension: AUC = trapz(trapz(M)) producing: AUC = ...

AREA UNDER the CURVE

Defining your matrix as ‘M’, use the trapz function twice, once in each dimension: AUC = trapz(trapz(M)) producing: AUC = ...

etwa 12 Stunden ago | 0

| accepted

Answered

Fitting data in x,y to a known function

Use the fminsearch function to fit your data: x1 = linspace(1,32,32); y1 = [0.01 0.02 0.02 0.02 0.02 0.02 0.03 0.03 0.03 0.04...

Fitting data in x,y to a known function

Use the fminsearch function to fit your data: x1 = linspace(1,32,32); y1 = [0.01 0.02 0.02 0.02 0.02 0.02 0.03 0.03 0.03 0.04...

etwa 13 Stunden ago | 0

Answered

How can my function work?

Either change the function output to ‘Wans’: function Wans = fishing_load_factor(t) or change the ‘Wans’ within it to ‘W’.

How can my function work?

Either change the function output to ‘Wans’: function Wans = fishing_load_factor(t) or change the ‘Wans’ within it to ‘W’.

etwa 13 Stunden ago | 0

Answered

error bars in bar plot with categories

This seems to be an XOR situation. Apparently, it is possible to have categorical x-values or errorbar bars but not both. Th...

error bars in bar plot with categories

This seems to be an XOR situation. Apparently, it is possible to have categorical x-values or errorbar bars but not both. Th...

etwa 16 Stunden ago | 0

| accepted

Answered

Plot dB/dt vs. time by ODE45 (coupled differential equations)

One option is to loop through the ‘odes’ function with the time vector and solved values for ‘varsol’. A much easier option i...

Plot dB/dt vs. time by ODE45 (coupled differential equations)

One option is to loop through the ‘odes’ function with the time vector and solved values for ‘varsol’. A much easier option i...

etwa 17 Stunden ago | 1

| accepted

Answered

How to integrate after a derivative?

The result you want is not obvious. This runs without error, however you will need to determine if the result is what you wan...

How to integrate after a derivative?

The result you want is not obvious. This runs without error, however you will need to determine if the result is what you wan...

ein Tag ago | 0

Answered

Remove the 50 Hz Hum from a Signal

The designfilt call designs a second-order Butterworth filter. It appears to be correct when I analyse it with freqz. Without ...

Remove the 50 Hz Hum from a Signal

The designfilt call designs a second-order Butterworth filter. It appears to be correct when I analyse it with freqz. Without ...

ein Tag ago | 0

Answered

Fitting 2 data sets simultaneously using two different equations with some shared fit parameters.

Try this: global_fit_data = [A; B].'; % A and B are vectors of size 1X85 t = (0:10:840).'; global_fit_function = @(p,t) [p(3...

Fitting 2 data sets simultaneously using two different equations with some shared fit parameters.

Try this: global_fit_data = [A; B].'; % A and B are vectors of size 1X85 t = (0:10:840).'; global_fit_function = @(p,t) [p(3...

ein Tag ago | 0

| accepted

Answered

how to i change the x-axis from time to angle with this data?

Without your code, an exact respoinse is not possible. See for example XTick and XTickLabel.

how to i change the x-axis from time to angle with this data?

Without your code, an exact respoinse is not possible. See for example XTick and XTickLabel.

ein Tag ago | 0

Answered

How can I solve a set of equations using a function handle?

Try this: BigLambdaFunction = @(p,t,T) 1 - p(1).*((p(2)-(t-T))./(p(2)-t)).*exp((p(1).*T)./p(2)) biglambda = [ 0.0455 0....

How can I solve a set of equations using a function handle?

Try this: BigLambdaFunction = @(p,t,T) 1 - p(1).*((p(2)-(t-T))./(p(2)-t)).*exp((p(1).*T)./p(2)) biglambda = [ 0.0455 0....

ein Tag ago | 0

| accepted

Answered

@FinalProject_ode must return a column vector (solved)

Assuming all the elements are scalars, either transpose ‘dydt’ or put semicolons between the elements: dydt = [dPPARuFFA; dPPA...

@FinalProject_ode must return a column vector (solved)

Assuming all the elements are scalars, either transpose ‘dydt’ or put semicolons between the elements: dydt = [dPPARuFFA; dPPA...

2 Tage ago | 0

Answered

How to fix the code

If you want to set ‘N’ to the row size of ‘DATA’, this is preferable: N = size(DATA,1); Perhaps you intend to read the entir...

How to fix the code

If you want to set ‘N’ to the row size of ‘DATA’, this is preferable: N = size(DATA,1); Perhaps you intend to read the entir...

2 Tage ago | 0

| accepted

Answered

Should I shift my fft function?

It depends on the result you want. The shifted version plots the negative and positve frequencies (the Fourier transform is sym...

Should I shift my fft function?

It depends on the result you want. The shifted version plots the negative and positve frequencies (the Fourier transform is sym...

2 Tage ago | 0

| accepted

Answered

Matlab Outputting answers as fractions

You are still in the Symbolic Math Toolbox environment. Try one of these (depending on the rresult you want): X = vpa(linso...

Matlab Outputting answers as fractions

You are still in the Symbolic Math Toolbox environment. Try one of these (depending on the rresult you want): X = vpa(linso...

2 Tage ago | 1

| accepted

Answered

Multiplying a 3x3 matrix where values change with each iteration by a 3x1 matrix with values that iterate

What part of my Comment to your previous post Struggling with iterative matrix multiplication does not work?

Multiplying a 3x3 matrix where values change with each iteration by a 3x1 matrix with values that iterate

What part of my Comment to your previous post Struggling with iterative matrix multiplication does not work?

2 Tage ago | 0

Answered

Highpass Filter Sound Help

Store the filtered signals in a cell array (easiest). Then use the playblocking function to play them back one after the other ...

Highpass Filter Sound Help

Store the filtered signals in a cell array (easiest). Then use the playblocking function to play them back one after the other ...

2 Tage ago | 0

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Answered

Why it plots more than just one point and how do I get rid of them

The code plots more than one point because you told it to. Revised code: function xp=h2(t,x) xp=zeros(2,1); xp(1)=(x(2)) ...

Why it plots more than just one point and how do I get rid of them

The code plots more than one point because you told it to. Revised code: function xp=h2(t,x) xp=zeros(2,1); xp(1)=(x(2)) ...

2 Tage ago | 0

Answered

how to get rid of error which says too many output arguments

The ‘test3’ function needs to be: function xdot = test3(t,x) xdot(1)=x(2); xdot(2)= 10*(-2*x3 + x2); xdot=xdot'; end and ...

how to get rid of error which says too many output arguments

The ‘test3’ function needs to be: function xdot = test3(t,x) xdot(1)=x(2); xdot(2)= 10*(-2*x3 + x2); xdot=xdot'; end and ...

2 Tage ago | 0

Answered

Add error bars to grouped bar plot

See: Adding standard error bars to grouped bar graph

Add error bars to grouped bar plot

See: Adding standard error bars to grouped bar graph

2 Tage ago | 0

Answered

Multiple outputs from anonymous function

One option is to have the two outputs to one vector, then separate them in a subsequent assignment: demo_fcn = @(in) [in(1) in...

Multiple outputs from anonymous function

One option is to have the two outputs to one vector, then separate them in a subsequent assignment: demo_fcn = @(in) [in(1) in...

3 Tage ago | 0

Answered

How to show surface plot of 2D data?

Try this (with your own vectors): x = rand(10,1); % Create Data y = rand(10,1); ...

How to show surface plot of 2D data?

Try this (with your own vectors): x = rand(10,1); % Create Data y = rand(10,1); ...

3 Tage ago | 1

| accepted

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...

3 Tage 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...

3 Tage 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...

3 Tage 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, ...

3 Tage ago | 0

| accepted

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...

3 Tage ago | 0