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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

tf2ss not returning the correct State Space form

The result is correct. The exact configuration doesn’t matter, so long as all the matrices and vectors work together (and produ...

tf2ss not returning the correct State Space form

The result is correct. The exact configuration doesn’t matter, so long as all the matrices and vectors work together (and produ...

2 hours ago | 0

Answered

How do I generate a polynomial from roots that are repeated?

Iinteresting. I would expect no repeats, and complex conjugate values instead. Try this: rts = [ -0.7437 - 1.4178i ...

How do I generate a polynomial from roots that are repeated?

Iinteresting. I would expect no repeats, and complex conjugate values instead. Try this: rts = [ -0.7437 - 1.4178i ...

3 hours ago | 0

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Answered

add standard deviation value and text on bars

When I try to run your code, I get: Unrecognized function or variable 'X'. In its absence, try this: Y=[0.9 0.83 0.700;1.58...

add standard deviation value and text on bars

When I try to run your code, I get: Unrecognized function or variable 'X'. In its absence, try this: Y=[0.9 0.83 0.700;1.58...

6 hours ago | 0

Answered

ODE symbolic result plotting with fplot()

I am not certain what the problem is with the original function. If you simplify it first: phi = vpa(simplify(phi, 'Steps',...

ODE symbolic result plotting with fplot()

I am not certain what the problem is with the original function. If you simplify it first: phi = vpa(simplify(phi, 'Steps',...

6 hours ago | 0

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Answered

solve 3 order differential equations

Without seeing your ODE solver call, I cannot determine what the problem is. This runs without error for me (in R2020b): ...

solve 3 order differential equations

Without seeing your ODE solver call, I cannot determine what the problem is. This runs without error for me (in R2020b): ...

6 hours ago | 0

Answered

How can I mark wheezes on a plot?

Try something like this: wheezes = sort(randi(100, 10, 1)); % Create Data ws...

How can I mark wheezes on a plot?

Try something like this: wheezes = sort(randi(100, 10, 1)); % Create Data ws...

1 day ago | 0

Answered

Fprintf modification in matlab

Those are all preferences. See the Fonts section. There is no other way (to my knowledge) to change them. Also, I poste...

Fprintf modification in matlab

Those are all preferences. See the Fonts section. There is no other way (to my knowledge) to change them. Also, I poste...

1 day ago | 0

Answered

Need help.... How to plot sequences

The mod function and the colon,: operator are your friends!

Need help.... How to plot sequences

The mod function and the colon,: operator are your friends!

1 day ago | 0

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Answered

sampling time causes scaling of simulation results.

It may be appropriate to specify the the sampling time in the ss call. See Create Discrete-Time State-Space Model. Another p...

sampling time causes scaling of simulation results.

It may be appropriate to specify the the sampling time in the ss call. See Create Discrete-Time State-Space Model. Another p...

1 day ago | 0

Answered

How can we do for following fprintf formating

Try this: fprintf('\tx%c\n', char(178)) producinig: x² .

How can we do for following fprintf formating

Try this: fprintf('\tx%c\n', char(178)) producinig: x² .

1 day ago | 0

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Answered

How to Solve an Equation with Integral and Gamma functions?

I cannot achieve the result you describe. The code I used to (unsuccessfully) solve for it is: F = @(S) abs(S) - 0.01 * gam...

How to Solve an Equation with Integral and Gamma functions?

I cannot achieve the result you describe. The code I used to (unsuccessfully) solve for it is: F = @(S) abs(S) - 0.01 * gam...

2 days ago | 0

Answered

How to plot point clouds and linear regression line in the same plot?

Use the hold function.

How to plot point clouds and linear regression line in the same plot?

Use the hold function.

2 days ago | 0

Answered

How to Solve an Equation with an Integral for the Integral Range Parameter?

The gammainc function does not take complex arguments, so this is likely the best you can hope for: F = @(S) S - 0.01 * gammai...

How to Solve an Equation with an Integral for the Integral Range Parameter?

The gammainc function does not take complex arguments, so this is likely the best you can hope for: F = @(S) S - 0.01 * gammai...

2 days ago | 0

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Answered

ODE45 to solve a 2nd order differential equation with a parameter that changes in time

Interp[olate to find the appropriate values of ‘heave’ (that I call ‘heavet’ in ‘pitchODE’ ‘dxdt2’): function [dxdt] = pitchOD...

ODE45 to solve a 2nd order differential equation with a parameter that changes in time

Interp[olate to find the appropriate values of ‘heave’ (that I call ‘heavet’ in ‘pitchODE’ ‘dxdt2’): function [dxdt] = pitchOD...

2 days ago | 1

Answered

Percentiles without Statistics Toolbox

Try this: x = 3*randn(1,100)+5; % Create Data figure yyaxis left h = hi...

Percentiles without Statistics Toolbox

Try this: x = 3*randn(1,100)+5; % Create Data figure yyaxis left h = hi...

2 days ago | 0

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Answered

error with function bode

Rename your ‘conv.m’ file to something else, perhaps to ‘myconv.m’ or to something else that makes sense in the context of its u...

error with function bode

Rename your ‘conv.m’ file to something else, perhaps to ‘myconv.m’ or to something else that makes sense in the context of its u...

2 days ago | 0

Answered

Sorting time in 1 hour time slots.

One approach: A = datetime([zeros(100,4) randi(1440, 100, 1) zeros(100,1)]); % Create Data [H,~,ix] = unique(hour(A)...

Sorting time in 1 hour time slots.

One approach: A = datetime([zeros(100,4) randi(1440, 100, 1) zeros(100,1)]); % Create Data [H,~,ix] = unique(hour(A)...

3 days ago | 0

Answered

why is my plot plotting blank?

The value of ‘Cd’ is 0 in the code you posted, so ‘y’ is uniformly -Inf.

why is my plot plotting blank?

The value of ‘Cd’ is 0 in the code you posted, so ‘y’ is uniformly -Inf.

3 days ago | 0

Answered

How to get spatial frequency from FFT?

The Fourier transform neither knows nor cares whether the units of the independent variable are time, space, or anything else. ...

How to get spatial frequency from FFT?

The Fourier transform neither knows nor cares whether the units of the independent variable are time, space, or anything else. ...

3 days ago | 0

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Answered

How to plot particle trajectories and normalise to 0,0 origin?

This will normalise everycell to begin at (0,0): testdata = readmatrix('Amadeus Xu testdata.xlsx'); [Uid,~,ix] = unique(testd...

How to plot particle trajectories and normalise to 0,0 origin?

This will normalise everycell to begin at (0,0): testdata = readmatrix('Amadeus Xu testdata.xlsx'); [Uid,~,ix] = unique(testd...

3 days ago | 1

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Answered

How can I mix two signals in MATLAB?

Ther esult would appear to be a single-sideband suppresed-carrier signal (with only the upper sideband). See if the demod funct...

How can I mix two signals in MATLAB?

Ther esult would appear to be a single-sideband suppresed-carrier signal (with only the upper sideband). See if the demod funct...

4 days ago | 0

Answered

How can I import from Excel CSV

Use readtable to read it: T1 = readtable('sample.csv', 'VariableNamingRule','preserve', 'HeaderLines',22); The 'Headerlines' ...

How can I import from Excel CSV

Use readtable to read it: T1 = readtable('sample.csv', 'VariableNamingRule','preserve', 'HeaderLines',22); The 'Headerlines' ...

4 days ago | 0

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Answered

Smoothening the data of Iv loop

That looks like a hysteresis loop. See if the approach in how to find ascending and descending of hysteresis loop? will fit it ...

Smoothening the data of Iv loop

That looks like a hysteresis loop. See if the approach in how to find ascending and descending of hysteresis loop? will fit it ...

4 days ago | 0

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Answered

Fitting data with multiple inputs, ODE equation, and lsqnonlin

The fundamental problem is that lsqnonlin ~= lsqcurvefit! They are definitely not interchangable, and have different argument l...

Fitting data with multiple inputs, ODE equation, and lsqnonlin

The fundamental problem is that lsqnonlin ~= lsqcurvefit! They are definitely not interchangable, and have different argument l...

4 days ago | 1

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Answered

Matlab not recognizing dates

You did not mention how you were importing them. Try importing them this way: dv = {'202011' '202012'} datetime(d...

Matlab not recognizing dates

You did not mention how you were importing them. Try importing them this way: dv = {'202011' '202012'} datetime(d...

5 days ago | 0

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Answered

How to generate one square pulse?

Try this: sqpuls = @(t,t1,t2) (t>= t1) & (t <= t2); t = linspace(-1, 1); figure plot(t, sqpuls(t, -0.5, 0.5), '-r') gr...

How to generate one square pulse?

Try this: sqpuls = @(t,t1,t2) (t>= t1) & (t <= t2); t = linspace(-1, 1); figure plot(t, sqpuls(t, -0.5, 0.5), '-r') gr...

5 days ago | 0

Answered

How can I change the format of the answer?

I am not certain what you want. Try the vpa funciton: dphi = vpa(dphi, 5) producing: dphi = (1.25e-7*s^2 + 2.0438e-13)/...

How can I change the format of the answer?

I am not certain what you want. Try the vpa funciton: dphi = vpa(dphi, 5) producing: dphi = (1.25e-7*s^2 + 2.0438e-13)/...

5 days ago | 0

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Answered

Only getting zero as my output for ode45

Give it something other than 0 as the intial condition, for example: X0 = 0+eps; That worked when I tried it.

Only getting zero as my output for ode45

Give it something other than 0 as the intial condition, for example: X0 = 0+eps; That worked when I tried it.

5 days ago | 0

Answered

How to choose population and generations for GA?

I use an optimoptions structure for this. Example — PopSz = 500; Parms = 3; opts = optimoptions('ga', 'PopulationSize',Po...

How to choose population and generations for GA?

I use an optimoptions structure for this. Example — PopSz = 500; Parms = 3; opts = optimoptions('ga', 'PopulationSize',Po...

5 days ago | 0

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Answered

Array inputs in lsim function

Likely the easiest way is to create an (Nx3) matrix for ‘u’, with the constant inputs as constant vectors: N = 3501; u = [one...

Array inputs in lsim function

Likely the easiest way is to create an (Nx3) matrix for ‘u’, with the constant inputs as constant vectors: N = 3501; u = [one...

5 days ago | 0