11.632 total contributions since 2012

Hic sunt dracones!

PROFESSIONAL: Physician (M.D.): Diplomate of the American Board of Internal Medicine; M.Sc. Biomedical Engineering: Instrumentation, Signal Processing, Control, System Identification, Parameter Estimation

NON-PROFESSIONAL: Amateur Extra Class Amateur Radio Operator; Private Pilot, Airplane Single Engine Land, Instrument Rating Airplane; Gamer

NOTE: I do not respond to emails or personal messages, unless they are about my File Exchange contributions.

Answered

Quiver plot arrows hidden by surface plot?

I was considering something like this: x = linspace(-pi, pi, 20); h = x(2)-x(1); [X,Y] = ndgrid(x); Z = sin(X) .* cos(Y); ...

Quiver plot arrows hidden by surface plot?

I was considering something like this: x = linspace(-pi, pi, 20); h = x(2)-x(1); [X,Y] = ndgrid(x); Z = sin(X) .* cos(Y); ...

alrededor de 16 horas ago | 0

| accepted

Answered

Left and right sides have different number of elements

Both ‘R_e’ and ‘k’ are (1 x 10) vectors, so ‘f’ will also be a (1 x 10) vector. Try this: f(counter,:)=pipe(R_e,k); With t...

Left and right sides have different number of elements

Both ‘R_e’ and ‘k’ are (1 x 10) vectors, so ‘f’ will also be a (1 x 10) vector. Try this: f(counter,:)=pipe(R_e,k); With t...

alrededor de 19 horas ago | 0

| accepted

Answered

Linear Regression Code Formula

The polyfit function creates a least-squares fit of the data to a polynomial, given the independent and dependent variable data,...

Linear Regression Code Formula

The polyfit function creates a least-squares fit of the data to a polynomial, given the independent and dependent variable data,...

alrededor de 20 horas ago | 0

| accepted

Answered

how to generate a vector of zeros with 2 random successives cell containing ones

I have no idea what you want. Try this: z = zeros(1, 20); % Vector Of 20 Zeros idx = randi(n...

how to generate a vector of zeros with 2 random successives cell containing ones

I have no idea what you want. Try this: z = zeros(1, 20); % Vector Of 20 Zeros idx = randi(n...

alrededor de 21 horas ago | 0

Answered

Remove or hide the special Y-axis label

Change your axis call to: axis([0 8 0.94 1]) That should do what you want.

Remove or hide the special Y-axis label

Change your axis call to: axis([0 8 0.94 1]) That should do what you want.

1 día ago | 0

| accepted

Answered

Parameter estimation in ODE

You are trying to fit 5 columns of your differential equation to 4 columns of data. That will throw the error you got. Chang...

Parameter estimation in ODE

You are trying to fit 5 columns of your differential equation to 4 columns of data. That will throw the error you got. Chang...

1 día ago | 0

| accepted

Answered

How to remove NaN values from an array

Since you want the lines to be continuous, consider using the fillmissing (link) function to fill in the NaN values with numbers...

How to remove NaN values from an array

Since you want the lines to be continuous, consider using the fillmissing (link) function to fill in the NaN values with numbers...

1 día ago | 0

Answered

How do I output to the command window where the sum of the bars on the graph equal zero along the x axis

If fyou are referring to ‘PWA’, try this (after your plot call): for k = 1:size(PWA,1) PWA0(k) = interp1(PWA(k,:), x, 0, ...

How do I output to the command window where the sum of the bars on the graph equal zero along the x axis

If fyou are referring to ‘PWA’, try this (after your plot call): for k = 1:size(PWA,1) PWA0(k) = interp1(PWA(k,:), x, 0, ...

1 día ago | 0

Answered

Filling missing values of selected columns of a table with previous values

You most likely have to use fillmissing with each variable separately: Data.English = fillmissing(Data.English,'previous'); D...

Filling missing values of selected columns of a table with previous values

You most likely have to use fillmissing with each variable separately: Data.English = fillmissing(Data.English,'previous'); D...

1 día ago | 0

Answered

Why does the line for my graph not appear?

The reason is that ‘b’ has only the value at the end of the loop, so a scalar. Try this: syms x f = 5./((7+x).^2); a=0; ...

Why does the line for my graph not appear?

The reason is that ‘b’ has only the value at the end of the loop, so a scalar. Try this: syms x f = 5./((7+x).^2); a=0; ...

2 días ago | 0

| accepted

Answered

I am trying to accomplish this same task using the find() command but I'm not sure how.

Here is a version that uses a logical vector in place of the find function: x = 0:0.1:6; y = -5*x; lv = (2 <= x) & (x <= 4);...

I am trying to accomplish this same task using the find() command but I'm not sure how.

Here is a version that uses a logical vector in place of the find function: x = 0:0.1:6; y = -5*x; lv = (2 <= x) & (x <= 4);...

2 días ago | 1

| accepted

Answered

getting user input in title and legend

I would use the inputdlg (link) function. You can also use input.

getting user input in title and legend

I would use the inputdlg (link) function. You can also use input.

3 días ago | 0

Answered

sgolayfilt function not smoothing

Try it with a 3-degree polynomial rather than a 5-degree polynomial.

sgolayfilt function not smoothing

Try it with a 3-degree polynomial rather than a 5-degree polynomial.

3 días ago | 0

Answered

Surface Plot for ODE solution

You need to make a few changes in your code: w = 1; k=1; figure tspan = linspace(0, 5); % ...

Surface Plot for ODE solution

You need to make a few changes in your code: w = 1; k=1; figure tspan = linspace(0, 5); % ...

3 días ago | 0

| accepted

Answered

Solving Integrals with Matlab

There is an error in the anonymous function in ‘A3’, and since MATLAB is case-sensitive, ‘Intfun’ is not the same as ‘intfun’. ...

Solving Integrals with Matlab

There is an error in the anonymous function in ‘A3’, and since MATLAB is case-sensitive, ‘Intfun’ is not the same as ‘intfun’. ...

3 días ago | 0

Answered

Why is my Graph not plotting properly?

Add a counter. At the beginning of your while loop: k1 = 0; theta = 0; % Rotational arm angle % while(theta <= 360) % Bei...

Why is my Graph not plotting properly?

Add a counter. At the beginning of your while loop: k1 = 0; theta = 0; % Rotational arm angle % while(theta <= 360) % Bei...

3 días ago | 1

Answered

A Problem with function

Save it on your MATLAB search path of user files as: normalidade.m.

A Problem with function

Save it on your MATLAB search path of user files as: normalidade.m.

3 días ago | 0

| accepted

Answered

Phase Plot - Velocity vs Position

Unless I am not understanding your code, that would appear to be: figure(2) plot(y, v) grid xlabel('Position') yleabel('Ve...

Phase Plot - Velocity vs Position

Unless I am not understanding your code, that would appear to be: figure(2) plot(y, v) grid xlabel('Position') yleabel('Ve...

4 días ago | 0

Answered

Fsurf plot wrong when x coefficient is 0

The fsurf function cannot guess what you are thinking. Try this version of your code: syms x y z u v f1(v) = 214.906098118...

Fsurf plot wrong when x coefficient is 0

The fsurf function cannot guess what you are thinking. Try this version of your code: syms x y z u v f1(v) = 214.906098118...

4 días ago | 0

| accepted

Answered

Frequency scale in fft after zero filling (odd/even number of data)

I am not certain what you are doing. One way to make the frequencies equal would be to use the second argument, ‘n’, in the ff...

Frequency scale in fft after zero filling (odd/even number of data)

I am not certain what you are doing. One way to make the frequencies equal would be to use the second argument, ‘n’, in the ff...

4 días ago | 1

| accepted

Answered

How do I extrapolate a point from a generated graph.

The easiest way is to use the interp1 (link) function to get the time when the car has travelled 250m.

How do I extrapolate a point from a generated graph.

The easiest way is to use the interp1 (link) function to get the time when the car has travelled 250m.

4 días ago | 0

| accepted

Answered

How to use a subplot in a for loop

I am not certain what you want. Try this: syms y x y = acos(x); n = [3 5 7] ttlc = {'y', 'T3(x)', 'T5(x)', 'T7(x)'}; ho...

How to use a subplot in a for loop

I am not certain what you want. Try this: syms y x y = acos(x); n = [3 5 7] ttlc = {'y', 'T3(x)', 'T5(x)', 'T7(x)'}; ho...

4 días ago | 0

Answered

How do I get some part of my boxplot labels italic? I can not change the Interpreter to 'tex' somehow? Why? How can I work around?

Use the 'TickLabelInterpreter' property: dados = rand(100,2); boxplot(dados,'labels',{'\bf\it{IDEB}__{2007}','\bf Efficiencie...

How do I get some part of my boxplot labels italic? I can not change the Interpreter to 'tex' somehow? Why? How can I work around?

Use the 'TickLabelInterpreter' property: dados = rand(100,2); boxplot(dados,'labels',{'\bf\it{IDEB}__{2007}','\bf Efficiencie...

4 días ago | 0

| accepted

Answered

MATLAB system of ODEs

Please see: System of 2 differential equations (link).

MATLAB system of ODEs

Please see: System of 2 differential equations (link).

5 días ago | 1

| accepted

Answered

i am trying to put my level curves and gradient vectors on same figure but i can't

Your current approach is not going to work. Try this instead: f=@(x,y) 16*y.^2 + 9*x.^2; g = @(z) gradient(z) figure(1) ...

i am trying to put my level curves and gradient vectors on same figure but i can't

Your current approach is not going to work. Try this instead: f=@(x,y) 16*y.^2 + 9*x.^2; g = @(z) gradient(z) figure(1) ...

5 días ago | 1

| accepted

Answered

How to change color for stacked bar chart

Try this: y = [50 50; 25 75; 30 70]; figure ba = bar(y,'stacked', 'FaceColor','flat'); ba(1).CData = [0.3 0.3 0.7]; ba(2...

How to change color for stacked bar chart

Try this: y = [50 50; 25 75; 30 70]; figure ba = bar(y,'stacked', 'FaceColor','flat'); ba(1).CData = [0.3 0.3 0.7]; ba(2...

5 días ago | 0

| accepted

Answered

Does audioread not return a vector?

It depends on your audio file. A stereophonic signal will return an (N x 2) matrix, with the first column being the left channe...

Does audioread not return a vector?

It depends on your audio file. A stereophonic signal will return an (N x 2) matrix, with the first column being the left channe...

6 días ago | 0

| accepted

Answered

amplitude plot not working

Your ‘A’ vector has purely imaginary components. Try this: plot(omega, imag(A))

amplitude plot not working

Your ‘A’ vector has purely imaginary components. Try this: plot(omega, imag(A))

6 días ago | 0

Answered

How would I add labels to points?

Use the text (link) function. You will likely also need the sprintf function.

How would I add labels to points?

Use the text (link) function. You will likely also need the sprintf function.

6 días ago | 0

| accepted

Answered

RMSE of sequences in cell arrays with different length

I am not certain what final result you want. This should get you started: subt = cellfun(@minus, YTest, YPred, 'Uni',0); ...

RMSE of sequences in cell arrays with different length

I am not certain what final result you want. This should get you started: subt = cellfun(@minus, YTest, YPred, 'Uni',0); ...

6 días ago | 0