12.751 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

How to rearrange the output variables for matlabFunction()?

I can’t run the code you posted, since it generates significant errors about matrix size multiplication. However, a simple ex...

How to rearrange the output variables for matlabFunction()?

I can’t run the code you posted, since it generates significant errors about matrix size multiplication. However, a simple ex...

alrededor de 12 horas ago | 1

| accepted

Answered

solve an equation using solve() produces an array instead of a unique value

The result is correct. There are three roots. Plot it to see the result: syms h d = 32*h + 200*(32*h - 8)*((4*h - 1)^2 -...

solve an equation using solve() produces an array instead of a unique value

The result is correct. There are three roots. Plot it to see the result: syms h d = 32*h + 200*(32*h - 8)*((4*h - 1)^2 -...

alrededor de 13 horas ago | 0

| accepted

Answered

Error while solving a coupled system of ODE

Your ‘DM_bacteria’ function must return a column vector output. This worked when I ran it just now: function [dxdt] = DM_ba...

Error while solving a coupled system of ODE

Your ‘DM_bacteria’ function must return a column vector output. This worked when I ran it just now: function [dxdt] = DM_ba...

alrededor de 14 horas ago | 1

Answered

Array indices must be positive integers or logical values

The problem: for k=0:M-1 The solution: for k=1:M In MATLAB, subscript indices begin at 1, not 0, and are defined as intege...

Array indices must be positive integers or logical values

The problem: for k=0:M-1 The solution: for k=1:M In MATLAB, subscript indices begin at 1, not 0, and are defined as intege...

alrededor de 15 horas ago | 0

| accepted

Answered

Wrong answer for sine function

Define ‘t’ in terms of days (or fractions of days). Try this: rforce = @(t) 0.3 + 0.2.*sin(2.*pi.*t/365 - pi/2); tdays =...

Wrong answer for sine function

Define ‘t’ in terms of days (or fractions of days). Try this: rforce = @(t) 0.3 + 0.2.*sin(2.*pi.*t/365 - pi/2); tdays =...

alrededor de 15 horas ago | 1

| accepted

Answered

Working With Matlab Tables

I created my own table to test my code. (I didn’t post it previously because the other two Answers had already appeared.) Th...

Working With Matlab Tables

I created my own table to test my code. (I didn’t post it previously because the other two Answers had already appeared.) Th...

alrededor de 16 horas ago | 0

Answered

Ploting two different vectors in the same figure

Use element-wise multiplication, then transpose ‘a’ and ‘b’ to use the references in your plot3 calls. Alos, specifically use t...

Ploting two different vectors in the same figure

Use element-wise multiplication, then transpose ‘a’ and ‘b’ to use the references in your plot3 calls. Alos, specifically use t...

alrededor de 16 horas ago | 0

| accepted

Answered

Understanding Figure Windows & Changing Their Apperances

According to the documentation on Figure Properties, Number is read-only. However, this appears to work: Stress = figure(34...

Understanding Figure Windows & Changing Their Apperances

According to the documentation on Figure Properties, Number is read-only. However, this appears to work: Stress = figure(34...

alrededor de 19 horas ago | 0

Answered

plot with a few sample marked.

Try these: x= 1:0.01:40; y = cos(x); L1 = y <= 0.5; % Logical Index: y <= 0.5 figure pl...

plot with a few sample marked.

Try these: x= 1:0.01:40; y = cos(x); L1 = y <= 0.5; % Logical Index: y <= 0.5 figure pl...

alrededor de 19 horas ago | 0

Answered

how can i save struct in file txt?

Use the save function to save it as a .mat file.

how can i save struct in file txt?

Use the save function to save it as a .mat file.

alrededor de 19 horas ago | 1

| accepted

Answered

Circle centers plot aren't in the same place as the circles in a figure

I cannot run your code. However, since ‘centersStrong’ is a two-column matrix of the x and y coordinates, your plot call woul...

Circle centers plot aren't in the same place as the circles in a figure

I cannot run your code. However, since ‘centersStrong’ is a two-column matrix of the x and y coordinates, your plot call woul...

alrededor de 22 horas ago | 0

| accepted

Answered

The question about DC component!

Removing the DC component is useful in showing the other peaks in the Fourier transform of your signal, if there is a very high ...

The question about DC component!

Removing the DC component is useful in showing the other peaks in the Fourier transform of your signal, if there is a very high ...

1 día ago | 0

| accepted

Answered

fprintf conversion character use \c or \s?

Putting character arrays and numeric variable types together in a matrix is not appropriate. Try this instead: countries = ...

fprintf conversion character use \c or \s?

Putting character arrays and numeric variable types together in a matrix is not appropriate. Try this instead: countries = ...

1 día ago | 0

Answered

Error when solving an equation involving a poisson pdf

Try this (instead of using the Symbolic Math Toolbox): lambda = fzero(@(lambda) poisspdf(10, lambda) - 0.1, 5) producing: l...

Error when solving an equation involving a poisson pdf

Try this (instead of using the Symbolic Math Toolbox): lambda = fzero(@(lambda) poisspdf(10, lambda) - 0.1, 5) producing: l...

1 día ago | 0

| accepted

Answered

Ploting solutions to linear equations

The ‘A*Y’ operation attempts to multiply (3x3) matrix ‘A’ by a (2x1) vector ‘Y’. That will just never work! The ‘Y’ vector m...

Ploting solutions to linear equations

The ‘A*Y’ operation attempts to multiply (3x3) matrix ‘A’ by a (2x1) vector ‘Y’. That will just never work! The ‘Y’ vector m...

1 día ago | 0

Answered

How to retrieve last 3 digits from each entry of a matrix of order 3 x 4 ?

Another approach: A = [35679, 35678, 35677, 35676; 35675, 35674, 35673, 35672; 35671, 35670, 35669, 35668]; Out = 1000*rem(A/...

How to retrieve last 3 digits from each entry of a matrix of order 3 x 4 ?

Another approach: A = [35679, 35678, 35677, 35676; 35675, 35674, 35673, 35672; 35671, 35670, 35669, 35668]; Out = 1000*rem(A/...

2 días ago | 0

Answered

Mean of 72720 rows in one column such that I can take mean of 720 rows separately.

Try this: data = (1:72720)'; % Create Column Vector To Test Code rdata = reshape(data, [], 7...

Mean of 72720 rows in one column such that I can take mean of 720 rows separately.

Try this: data = (1:72720)'; % Create Column Vector To Test Code rdata = reshape(data, [], 7...

2 días ago | 1

| accepted

Answered

insert rows and columns in a matrix

One approach: M = rand(3); Mz = zeros(size(M,1)+1, size(M,2)+1); Mz(1:size(M,1), 1:size(M,2)) = M; producing (here): Mz =...

insert rows and columns in a matrix

One approach: M = rand(3); Mz = zeros(size(M,1)+1, size(M,2)+1); Mz(1:size(M,1), 1:size(M,2)) = M; producing (here): Mz =...

2 días ago | 1

| accepted

Answered

Creating String Array Between Two Dates

Try this: date = '01-jan-2019'; EndDate = '03-feb-2019'; DateVec = datetime(date); EndDateVec = datetime(EndDate); DayArr ...

Creating String Array Between Two Dates

Try this: date = '01-jan-2019'; EndDate = '03-feb-2019'; DateVec = datetime(date); EndDateVec = datetime(EndDate); DayArr ...

2 días ago | 0

Answered

Function for ODE45 solver doesn't work

You have not provided enough information to determine what the problem is. However, considering that ‘Istim_sys’ may be a vecto...

Function for ODE45 solver doesn't work

You have not provided enough information to determine what the problem is. However, considering that ‘Istim_sys’ may be a vecto...

2 días ago | 0

Answered

Function doesn't return a vector from a vector input

‘Could someone tell me my mistake?’ You need to use the any or all functions in the if statements, depending on what you want...

Function doesn't return a vector from a vector input

‘Could someone tell me my mistake?’ You need to use the any or all functions in the if statements, depending on what you want...

3 días ago | 1

| accepted

Answered

Bode Plot - trasnfer function

Try this (your code slightly edited): s = tf('s'); G = ((1+s*1E-3))/((s*1E-2)*(1+s*1E-1)*(1+s*1E-5)); bode(G) ...

Bode Plot - trasnfer function

Try this (your code slightly edited): s = tf('s'); G = ((1+s*1E-3))/((s*1E-2)*(1+s*1E-1)*(1+s*1E-5)); bode(G) ...

3 días ago | 1

| accepted

Answered

Failure in initial objective function evaluation. FSOLVE cannot continue.

The ‘Y’ evaluation is missing a few multiplication(?) operators, and needs to do element-wise operations elsewhere: Y = B-((Q1...

Failure in initial objective function evaluation. FSOLVE cannot continue.

The ‘Y’ evaluation is missing a few multiplication(?) operators, and needs to do element-wise operations elsewhere: Y = B-((Q1...

3 días ago | 0

Answered

Question on how to use scatter3

The ‘Z’ vector can be anything, providing it is a vector of the same size as the others. Setting it equal to: Z = zeros(size(...

Question on how to use scatter3

The ‘Z’ vector can be anything, providing it is a vector of the same size as the others. Setting it equal to: Z = zeros(size(...

3 días ago | 0

| accepted

Answered

How do I plot these for loops?

Put them all in subplots, with the appropriate indexing: tspan = linspace(0, 5, 25); for k=1:5 y0 = 0; [t,y(:,k)] = ode45(@...

How do I plot these for loops?

Put them all in subplots, with the appropriate indexing: tspan = linspace(0, 5, 25); for k=1:5 y0 = 0; [t,y(:,k)] = ode45(@...

3 días ago | 0

| accepted

Answered

Other alternative than syms for differentiation and integration?

MATLAB is case-sensitive, so X ~= x. Try this: syms x; fun = x^3+2*x+10; dfundx = diff (fun,x); producing: dfundx = 3...

Other alternative than syms for differentiation and integration?

MATLAB is case-sensitive, so X ~= x. Try this: syms x; fun = x^3+2*x+10; dfundx = diff (fun,x); producing: dfundx = 3...

3 días ago | 0

Answered

Solving non linear equations sytem

The Symbolic Math Toolbox is not optimal for such problems. It is likely not worth the effort to see if a symbolic solution exi...

Solving non linear equations sytem

The Symbolic Math Toolbox is not optimal for such problems. It is likely not worth the effort to see if a symbolic solution exi...

4 días ago | 2

Answered

undefined variable error when the variable is there

Please note that: l ~= 1 You typed: for i = l:length(t) for j = l:length(x) however I believe you intended: for i =...

undefined variable error when the variable is there

Please note that: l ~= 1 You typed: for i = l:length(t) for j = l:length(x) however I believe you intended: for i =...

4 días ago | 0

| accepted

Answered

t(j) is coming up as an error when trying to graph values. what am i doing wrong

It doesn’t appear that you have defined ‘j’ anywhere before the loop. One possibility: iv = 0:0.1:t1; for j = 1:numel(iv) ...

t(j) is coming up as an error when trying to graph values. what am i doing wrong

It doesn’t appear that you have defined ‘j’ anywhere before the loop. One possibility: iv = 0:0.1:t1; for j = 1:numel(iv) ...

5 días ago | 0

| accepted