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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 can I solve non polynomial equations.

FIRST: see Getting Started. What you posted is not valid MATLAB code. There may be many solutions, depending on the initia...

how can I solve non polynomial equations.

FIRST: see Getting Started. What you posted is not valid MATLAB code. There may be many solutions, depending on the initia...

alrededor de 4 horas ago | 0

| accepted

Answered

Error using plot Data must be numeric, datetime, duration or an array convertible to double. Error in prueba3 (line 12) plot(x,Vol);

I have no idea what you want ‘x’ to be. Try this: figure fplot(Vol, [0 C]); Make appropriate changes to define ‘x’ (defin...

Error using plot Data must be numeric, datetime, duration or an array convertible to double. Error in prueba3 (line 12) plot(x,Vol);

I have no idea what you want ‘x’ to be. Try this: figure fplot(Vol, [0 C]); Make appropriate changes to define ‘x’ (defin...

alrededor de 4 horas ago | 0

Answered

How do i find points where slope is zero.

If you want to use the gradient function to find the inflection points, and since you are dealing with finite-precision values, ...

How do i find points where slope is zero.

If you want to use the gradient function to find the inflection points, and since you are dealing with finite-precision values, ...

alrededor de 6 horas ago | 0

Answered

Insert zero in an array when a certain value is exceeded

The vectors do not have the same numbers of elements. Correcting for that: Y= [175 175 175 175 175 175 175 175 175 175 175 ...

Insert zero in an array when a certain value is exceeded

The vectors do not have the same numbers of elements. Correcting for that: Y= [175 175 175 175 175 175 175 175 175 175 175 ...

alrededor de 7 horas ago | 0

Answered

How to user polarplot when theta and rho are matrix?

It depends what they are. Using pol2cart and then plotting them using a Cartesian plot is an option, although you would have to...

How to user polarplot when theta and rho are matrix?

It depends what they are. Using pol2cart and then plotting them using a Cartesian plot is an option, although you would have to...

alrededor de 8 horas ago | 0

Answered

how to plot f (x,y) at x=1

See if this does what you want: y = ...; % Choose A Vector fy = f(1,y); figure plot(y,...

how to plot f (x,y) at x=1

See if this does what you want: y = ...; % Choose A Vector fy = f(1,y); figure plot(y,...

alrededor de 8 horas ago | 0

Answered

How do I make a 21x21 array from the center of a 200x150 array?

I called your image ‘parrot grayscale.png’. I = imread('parrot grayscale.png'); [r,c] = size(I); sr = fix((r-21)/2); sc = ...

How do I make a 21x21 array from the center of a 200x150 array?

I called your image ‘parrot grayscale.png’. I = imread('parrot grayscale.png'); [r,c] = size(I); sr = fix((r-21)/2); sc = ...

alrededor de 10 horas ago | 0

Answered

how can I fit the following points to equation "f(x) = a + b*exp(-c*x)"

Try this: x = [30, 60, 90, 120, 150, 180, 240, 270, 300, 330, 360, 390, 420]; y = [333.15, 332.15, 330.65, 330.15, 329.15, 32...

how can I fit the following points to equation "f(x) = a + b*exp(-c*x)"

Try this: x = [30, 60, 90, 120, 150, 180, 240, 270, 300, 330, 360, 390, 420]; y = [333.15, 332.15, 330.65, 330.15, 329.15, 32...

alrededor de 12 horas ago | 0

Answered

Remove noise from EMG signal

Those are actually sampling artifacts, not parts of the EMG signal. Probably the best way to deal with them is to use findpeaks...

Remove noise from EMG signal

Those are actually sampling artifacts, not parts of the EMG signal. Probably the best way to deal with them is to use findpeaks...

alrededor de 17 horas ago | 0

Answered

Why, Array indices must be positive integers or logical values

It is saying that because ‘r’ is not an integer, and even if it was, there are only some instances in which ‘r/12’ would be an i...

Why, Array indices must be positive integers or logical values

It is saying that because ‘r’ is not an integer, and even if it was, there are only some instances in which ‘r/12’ would be an i...

1 día ago | 2

Answered

Segmentation of a signal 184148x1

See if the buffer function will do what you want.

Segmentation of a signal 184148x1

See if the buffer function will do what you want.

1 día ago | 1

Answered

Why do i get this error? can you explain it to me please

You have a script that you named ‘image’: C:\Users\WASD\Documents\MATLAB\image.m That is the problem. The solution is to ren...

Why do i get this error? can you explain it to me please

You have a script that you named ‘image’: C:\Users\WASD\Documents\MATLAB\image.m That is the problem. The solution is to ren...

1 día ago | 1

Answered

Adding two matrix together

Try this: A = rand(1,30); % Create Vector B = [zeros(1,30) rand(1,30)]; ...

Adding two matrix together

Try this: A = rand(1,30); % Create Vector B = [zeros(1,30) rand(1,30)]; ...

1 día ago | 1

| accepted

Answered

Use fprintf for data from a table

Try this: M = [3 7 2005 30 1 4 2005 35 1 5 2005 24 2 6 2005 25]; MDate = datetime(M(:,3),M(:,2),M(:,1)); ...

Use fprintf for data from a table

Try this: M = [3 7 2005 30 1 4 2005 35 1 5 2005 24 2 6 2005 25]; MDate = datetime(M(:,3),M(:,2),M(:,1)); ...

1 día ago | 1

| accepted

Answered

Parameter Estimation First Order ODE

See: Parameter fit differential equation to dataset for a relevant example of how to approach this problem.

Parameter Estimation First Order ODE

See: Parameter fit differential equation to dataset for a relevant example of how to approach this problem.

1 día ago | 0

Answered

What is wrong with this code?

You forgot to use element-wise division ... P = - ( (0.2*0.5)./Vf).*( (1 - sqrt(Vf/0.5))./( (16/pi^3)*(200^2/181e9).*sqrt(0.85....

What is wrong with this code?

You forgot to use element-wise division ... P = - ( (0.2*0.5)./Vf).*( (1 - sqrt(Vf/0.5))./( (16/pi^3)*(200^2/181e9).*sqrt(0.85....

2 días ago | 0

| accepted

Answered

Legend function does not work in R2019b

It was pointed out recently in another Question with a problem similar to yours that: opengl software is likely the appropria...

Legend function does not work in R2019b

It was pointed out recently in another Question with a problem similar to yours that: opengl software is likely the appropria...

2 días ago | 1

| accepted

Answered

how to plot percentage?

Use the 'Normalization','probability' name-value pair argument in your histogram call.

how to plot percentage?

Use the 'Normalization','probability' name-value pair argument in your histogram call.

2 días ago | 0

| accepted

Answered

Finding frequency and duration of an audio signal

You specified it to be 1 kHz, and 1 second duration, so it is just that: fs=24000.0; % Sampling rate t=0:1/fs:1; % One sampl...

Finding frequency and duration of an audio signal

You specified it to be 1 kHz, and 1 second duration, so it is just that: fs=24000.0; % Sampling rate t=0:1/fs:1; % One sampl...

2 días ago | 0

Answered

Solving system of equations for different combinations of symbolic variables

I am not certain what result you want. Try this: syms x y A = sym('x',[3,1]); C = sym('y',[3,1]); A(1) = 3; A(3) = 4; ...

Solving system of equations for different combinations of symbolic variables

I am not certain what result you want. Try this: syms x y A = sym('x',[3,1]); C = sym('y',[3,1]); A(1) = 3; A(3) = 4; ...

2 días ago | 0

Answered

Shade Area Between 2 Tabulated Plots.

This is as close as I can get: Y_Values = readtable(UserDir,'Sheet',SheetNameA,'Range','A2:A150','ReadVariableNames',0); X_Va...

Shade Area Between 2 Tabulated Plots.

This is as close as I can get: Y_Values = readtable(UserDir,'Sheet',SheetNameA,'Range','A2:A150','ReadVariableNames',0); X_Va...

3 días ago | 1

| accepted

Answered

Find delta 99 of the boundary layer

See if the findchangepts or ischange functions will do what you want. You may need to invert them (plot y vs Ux) for them to wo...

Find delta 99 of the boundary layer

See if the findchangepts or ischange functions will do what you want. You may need to invert them (plot y vs Ux) for them to wo...

3 días ago | 1

| accepted

Answered

Solving an nonlinear equation

See if the Optimization Toolbox fsolve function can do what you want.

Solving an nonlinear equation

See if the Optimization Toolbox fsolve function can do what you want.

3 días ago | 0

Answered

textscan not reading all rows.

Without having your text file, it is not possible to provide specific code to read it. However, it is possilbe that that there ...

textscan not reading all rows.

Without having your text file, it is not possible to provide specific code to read it. However, it is possilbe that that there ...

3 días ago | 0

Answered

Speech processing. voice signal

See if the buffer function will do what you want.

Speech processing. voice signal

See if the buffer function will do what you want.

4 días ago | 0

Answered

Can not run function, written wrong?

The order is reversed. The ‘x’ variable needs to be assigned before calculating ‘y’, since ‘y’ depends on ‘x’.

Can not run function, written wrong?

The order is reversed. The ‘x’ variable needs to be assigned before calculating ‘y’, since ‘y’ depends on ‘x’.

4 días ago | 0

| accepted

Answered

Parameter fit differential equation to dataset

I have discussed this several times over the years. See for example Monod kinetics and curve fitting and Parameter Estimation f...

Parameter fit differential equation to dataset

I have discussed this several times over the years. See for example Monod kinetics and curve fitting and Parameter Estimation f...

4 días ago | 0

| accepted

Answered

How can I rearrange a table with different types of data?

See if the unstack function will do what you want.

How can I rearrange a table with different types of data?

See if the unstack function will do what you want.

4 días ago | 1

Answered

I need help to modify my optimization code

Note that in the ‘% Parameters’ section, you are creating new random numbers in every call to ‘objective_function’. The optim...

I need help to modify my optimization code

Note that in the ‘% Parameters’ section, you are creating new random numbers in every call to ‘objective_function’. The optim...

5 días ago | 0

| accepted

Answered

How to convert XLim day data to monthly?

Since you’re using datetime arrays, using the xtickformat function and specifically using 'MM' or 'MMM' as described in the date...

How to convert XLim day data to monthly?

Since you’re using datetime arrays, using the xtickformat function and specifically using 'MM' or 'MMM' as described in the date...

5 días ago | 1