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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

How to change X axis in the form of percentage

Try something like this — x = linspace(77, 146); y = -60 - 15*sin(2*pi*x/50); figure plot(x, y) Ax = gca; xt = Ax.XTick...

How to change X axis in the form of percentage

Try something like this — x = linspace(77, 146); y = -60 - 15*sin(2*pi*x/50); figure plot(x, y) Ax = gca; xt = Ax.XTick...

etwa eine Stunde ago | 1

Answered

How do I allow the user to save all the images of the floorplans they've created?

Perhaps — saveas(gcf, sprintf("floorPlan_%d.png",b) ); will save more of them.

How do I allow the user to save all the images of the floorplans they've created?

Perhaps — saveas(gcf, sprintf("floorPlan_%d.png",b) ); will save more of them.

etwa eine Stunde ago | 0

Answered

Plotting a filter as a function of cyclic frequency using freqz()

Your approach is correct. The reason the freqz plot did not look correct is that you were passing the filtered signal to it, no...

Plotting a filter as a function of cyclic frequency using freqz()

Your approach is correct. The reason the freqz plot did not look correct is that you were passing the filtered signal to it, no...

etwa 9 Stunden ago | 0

| accepted

Answered

Coupled second order differential equation

Start by writing the equations using the Symbolic Math Toolbox. Specifically, see the documentation on the dsolve function. ...

Coupled second order differential equation

Start by writing the equations using the Symbolic Math Toolbox. Specifically, see the documentation on the dsolve function. ...

etwa 13 Stunden ago | 0

Answered

ode45 not working

There are a few errors, all easily solved. Try this — m = 5; g = 9.81; r = 0.470; I = 0.37; ks = 0.012; dt = 0.01; ...

ode45 not working

There are a few errors, all easily solved. Try this — m = 5; g = 9.81; r = 0.470; I = 0.37; ks = 0.012; dt = 0.01; ...

etwa 16 Stunden ago | 0

Answered

How to tell matlab that y is a function of x; not a constant

In the initial syms call, declare ‘y(x)’ instead of ‘y’ — syms x y(x) z z=x*y; Dz = diff(z,x) ...

How to tell matlab that y is a function of x; not a constant

In the initial syms call, declare ‘y(x)’ instead of ‘y’ — syms x y(x) z z=x*y; Dz = diff(z,x) ...

etwa 20 Stunden ago | 1

| accepted

Answered

Locating rising peaks of variable amplitude pulses

I am not certain what you are doing, or what the ‘overlaid pulses situation’ means. There appears to be a significant amount ...

Locating rising peaks of variable amplitude pulses

I am not certain what you are doing, or what the ‘overlaid pulses situation’ means. There appears to be a significant amount ...

etwa 22 Stunden ago | 0

Answered

How do I make a low-pass filter on this data set?

For an EKG, use the bandpass function with the lower cutoff at 1.5 Hz and the upper cutoff between 45 Hz (if there is mains or p...

How do I make a low-pass filter on this data set?

For an EKG, use the bandpass function with the lower cutoff at 1.5 Hz and the upper cutoff between 45 Hz (if there is mains or p...

ein Tag ago | 0

Answered

Adding text to each subplots

Use xlim and ylim to make the text positions relative to the axes — x1 = linspace(0,10, 25); y1 = exp(-0.1*x1); x2 = linspac...

Adding text to each subplots

Use xlim and ylim to make the text positions relative to the axes — x1 = linspace(0,10, 25); y1 = exp(-0.1*x1); x2 = linspac...

ein Tag ago | 0

| accepted

Answered

Error in App Designer " Undefined function 'sym2poly' for input arguments of type 'char'.."

Apart from the app code, apparently the numerator and denominator polynomials are not being transofmred into symbolic variables....

Error in App Designer " Undefined function 'sym2poly' for input arguments of type 'char'.."

Apart from the app code, apparently the numerator and denominator polynomials are not being transofmred into symbolic variables....

ein Tag ago | 1

| accepted

Answered

How to get tfest() to focus on a frequency range (or is something else wrong)?

Without any data or code, and since I have no idea how that was plotted, the only solution I can offer is to use the compare fun...

How to get tfest() to focus on a frequency range (or is something else wrong)?

Without any data or code, and since I have no idea how that was plotted, the only solution I can offer is to use the compare fun...

ein Tag ago | 0

Answered

CIplot unable to fill on log-x axis

I am not certain what you are doing. However in many situations, it is easier to initially plot in a linear scale, then afterwa...

CIplot unable to fill on log-x axis

I am not certain what you are doing. However in many situations, it is easier to initially plot in a linear scale, then afterwa...

ein Tag ago | 0

| accepted

Answered

Numerical integration using Trapz

That should produce one scalar value as ‘F’, so the subscripts are not necessary. I would do something like this — F = trap...

Numerical integration using Trapz

That should produce one scalar value as ‘F’, so the subscripts are not necessary. I would do something like this — F = trap...

2 Tage ago | 0

| accepted

Answered

Data is not importing? SOS

It is not importing because the correct approach to reading .wav files is to use audioread. Try that. It should do what you ...

Data is not importing? SOS

It is not importing because the correct approach to reading .wav files is to use audioread. Try that. It should do what you ...

2 Tage ago | 0

Answered

unable to solve with respect to y

Try this — syms s x y(x) y0 Dy0 C1 C2 Dy = diff(y); D2y = diff(Dy); ode=(x^2*D2y)-(3*x*Dy)+(3*y)==(2*x^4*(exp(x))) y(x,C1,...

unable to solve with respect to y

Try this — syms s x y(x) y0 Dy0 C1 C2 Dy = diff(y); D2y = diff(Dy); ode=(x^2*D2y)-(3*x*Dy)+(3*y)==(2*x^4*(exp(x))) y(x,C1,...

2 Tage ago | 0

Answered

What would be a best interpolation method to get test data for a specific temperature?

I would just use interp1 — TestData = sortrows(randi([0 200], 15, 4),1) InterpTemps = [0 40 100]; Interp_234 = interp1(TestD...

What would be a best interpolation method to get test data for a specific temperature?

I would just use interp1 — TestData = sortrows(randi([0 200], 15, 4),1) InterpTemps = [0 40 100]; Interp_234 = interp1(TestD...

3 Tage ago | 0

Answered

xlsread isn't storing all the cell values from a column

Try something like this — T1 = readtable('YourExcelFile.xlsx', 'Range','A1:E19') That will import everything as a table, and ...

xlsread isn't storing all the cell values from a column

Try something like this — T1 = readtable('YourExcelFile.xlsx', 'Range','A1:E19') That will import everything as a table, and ...

3 Tage ago | 0

| accepted

Answered

Output argument "K" (and maybe others) not assigned during call to "linear_kernel".

Why not just — K = dot(x1,x2) instead? See the documentation on the dot function for details.

Output argument "K" (and maybe others) not assigned during call to "linear_kernel".

Why not just — K = dot(x1,x2) instead? See the documentation on the dot function for details.

3 Tage ago | 0

| accepted

Answered

The value of equation

I have absolutely no clue as to what you want. Try this — syms x u x3 %x = (0:1:4) L1 = 8; L =...

The value of equation

I have absolutely no clue as to what you want. Try this — syms x u x3 %x = (0:1:4) L1 = 8; L =...

3 Tage ago | 0

Answered

Calculating the Standard Deviation

Two options are to either calculate it directly, or use the normalize funciton — y = readmatrix('https://www.mathworks.com/mat...

Calculating the Standard Deviation

Two options are to either calculate it directly, or use the normalize funciton — y = readmatrix('https://www.mathworks.com/mat...

3 Tage ago | 0

Answered

How to Numerically Integrate Vector with Timestep

Use the trapz function (or cumtrapz, dependng on the result you want), The vector with respect to the numeric integration (time...

How to Numerically Integrate Vector with Timestep

Use the trapz function (or cumtrapz, dependng on the result you want), The vector with respect to the numeric integration (time...

3 Tage ago | 1

Answered

Getting the area of a surface integral from Matlab

See if simplifying it does what you want — syms phi the x = cos(phi).*sin(the); y = sin(phi).*sin(the); z = cos(the); dens...

Getting the area of a surface integral from Matlab

See if simplifying it does what you want — syms phi the x = cos(phi).*sin(the); y = sin(phi).*sin(the); z = cos(the); dens...

3 Tage ago | 1

| accepted

Answered

How to process xlsx with readtable for graphs/plots

One approach is to use groupsummary to aggregate the data — T1 = readtable('https://www.mathworks.com/matlabcentral/answers/up...

How to process xlsx with readtable for graphs/plots

One approach is to use groupsummary to aggregate the data — T1 = readtable('https://www.mathworks.com/matlabcentral/answers/up...

3 Tage ago | 0

| accepted

Answered

Solve for one variable

It really is not at all different, except the format. Examing it — syms p A=0.1199; At=0.112; y=1.43; P1=119; Error =0...

Solve for one variable

It really is not at all different, except the format. Examing it — syms p A=0.1199; At=0.112; y=1.43; P1=119; Error =0...

4 Tage ago | 0

Answered

Can you have lines between circles on a scatter plot?

Try this — a = [50:199]; b = [75:224]; i = [1:150]; scatter( i, [a;b] ) [ia,ib] = (ismember(a,b)); aidx = find(ia); hold...

Can you have lines between circles on a scatter plot?

Try this — a = [50:199]; b = [75:224]; i = [1:150]; scatter( i, [a;b] ) [ia,ib] = (ismember(a,b)); aidx = find(ia); hold...

4 Tage ago | 0

| accepted

Answered

empty sym: 0-by-1. please help me

a=9.61; b=0.16; fc=2000*10^6; c=300*10^6; A= 10^(1/10)-10^(20/10); B=(20*log10(4*pi*fc/c))+10^(20/10) syms R real; y=...

empty sym: 0-by-1. please help me

a=9.61; b=0.16; fc=2000*10^6; c=300*10^6; A= 10^(1/10)-10^(20/10); B=(20*log10(4*pi*fc/c))+10^(20/10) syms R real; y=...

4 Tage ago | 1

| accepted

Answered

Help with Laplace ODE

Try this — syms t y(t) Y(s) Dy0 a b y0 Dy1 = diff(y,t,1); eqn = laplace(Dy1== a*sinh(a*t)) eqn = subs(eqn, {laplace(y(t), ...

Help with Laplace ODE

Try this — syms t y(t) Y(s) Dy0 a b y0 Dy1 = diff(y,t,1); eqn = laplace(Dy1== a*sinh(a*t)) eqn = subs(eqn, {laplace(y(t), ...

4 Tage ago | 1

| accepted

Answered

FFT results correct for following filtering?

It is my code ( apparently copied from is the FFT right? ) and I do not see any mistakes in it! That signal and ‘CH0’ here ar...

FFT results correct for following filtering?

It is my code ( apparently copied from is the FFT right? ) and I do not see any mistakes in it! That signal and ‘CH0’ here ar...

4 Tage ago | 1

| accepted

Answered

Error in ode45 (line 115) and odearguments (line 90)

First, do not use global variables! Pass extra parameters as additional parameters. See Passing Extra Parameters for details....

Error in ode45 (line 115) and odearguments (line 90)

First, do not use global variables! Pass extra parameters as additional parameters. See Passing Extra Parameters for details....

4 Tage ago | 0

| accepted

Answered

Fourier series using matlab

We can’t correct it because you posted an image of it rather the actual code. The solution is straightforward nevertheless — ...

Fourier series using matlab

We can’t correct it because you posted an image of it rather the actual code. The solution is straightforward nevertheless — ...

4 Tage ago | 1