Answered

Solving nonlinear DE by reduction of order on matlab

There are some typos in your description of the problem. Here the correct version % your ODE - note that (y(1) and y(2) are exc...

Solving nonlinear DE by reduction of order on matlab

There are some typos in your description of the problem. Here the correct version % your ODE - note that (y(1) and y(2) are exc...

12 meses ago | 0

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Answered

creating array based in another array

Here a possible solution, where all arrays you want are in the columns of matrix a2 % number of entries in array 1 n = 5; % c...

creating array based in another array

Here a possible solution, where all arrays you want are in the columns of matrix a2 % number of entries in array 1 n = 5; % c...

12 meses ago | 0

Answered

Warning: Matrix is singular to working precision.

The matrix is singular because the first three rows are linearly dependent. For example you can obtain row 1 as I guess there...

Warning: Matrix is singular to working precision.

The matrix is singular because the first three rows are linearly dependent. For example you can obtain row 1 as I guess there...

12 meses ago | 0

Answered

how can i let all number in matrix X between 0~1?

If you want to scale your output in [0 1] you can use this X1 = (X-min(X))/sum(X-min(X)); in fact >> sum(X1) ans = ...

how can i let all number in matrix X between 0~1?

If you want to scale your output in [0 1] you can use this X1 = (X-min(X))/sum(X-min(X)); in fact >> sum(X1) ans = ...

12 meses ago | 0

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Answered

how to shift the plotting graph?

Not sure if it is what you want, but you can change the x-axis limits in this way: set(gca,'xLim',[5 20]) to show the portion ...

how to shift the plotting graph?

Not sure if it is what you want, but you can change the x-axis limits in this way: set(gca,'xLim',[5 20]) to show the portion ...

12 meses ago | 0

Question

Real time GMRES convergence and stop callback

Dear Matlab users, I usually solve large linear problems using gmres. These simulations could last for several tens of hours. T...

12 meses ago | 0 answers | 0

Answered

Population growth in 7 years

Below you can find the output of the following code % rate r = 0.0063; % years t = 7; % initial population a = 5e6; t =...

Population growth in 7 years

Below you can find the output of the following code % rate r = 0.0063; % years t = 7; % initial population a = 5e6; t =...

alrededor de 1 año ago | 1

Question

Problem with Simscape variable visibility

Hi all, I have created a simulink model of a circuit using simscape electrical elements. I have also created two callbacks, Ini...

más de 1 año ago | 1 answer | 0

Answered

how to find parallel of resistors

Maybe it's too late for the OP, but for the records, I usually use an anonymous function with multiple inputs % ananymous paral...

how to find parallel of resistors

Maybe it's too late for the OP, but for the records, I usually use an anonymous function with multiple inputs % ananymous paral...

más de 1 año ago | 0

Answered

Nonlinear equation numerical solution

% params C = 1.2; D = 9420; E = -2.0; B = 0.1973; y0 =...

Nonlinear equation numerical solution

% params C = 1.2; D = 9420; E = -2.0; B = 0.1973; y0 =...

alrededor de 2 años ago | 0

Answered

Plotting a taylor series function of x^(1/3) centred at x=1728

One option is to use the built-in taylor function in symbolic math toolbox. If you want to use your strategy, there are some is...

Plotting a taylor series function of x^(1/3) centred at x=1728

One option is to use the built-in taylor function in symbolic math toolbox. If you want to use your strategy, there are some is...

alrededor de 2 años ago | 0

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Answered

Memory efficient alternative for meshgrid?

This is how to make the three-loop version analogous to the meshgrid version % some dummy values N = 300; x = linspace(1,10,N...

Memory efficient alternative for meshgrid?

This is how to make the three-loop version analogous to the meshgrid version % some dummy values N = 300; x = linspace(1,10,N...

alrededor de 2 años ago | 0

Answered

Sorting Equal Elements of Matrix into Groups in Cell Array

I had the same problem to detect isolated nodes in a graph: conncomp is the matlab command that gets the job done: % create the...

Sorting Equal Elements of Matrix into Groups in Cell Array

I had the same problem to detect isolated nodes in a graph: conncomp is the matlab command that gets the job done: % create the...

alrededor de 2 años ago | 0

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Answered

Error using / Matrix dimensions must agree...

f is a vector, as well as W. So you must use the dotted version of the division (that is ./ that performs the operation elementw...

Error using / Matrix dimensions must agree...

f is a vector, as well as W. So you must use the dotted version of the division (that is ./ that performs the operation elementw...

alrededor de 2 años ago | 0

Question

Copy Matlab Command Window without diary

Hi everyone, I would like to add an optional function command at the end of a script that logs the command window to a file. I...

alrededor de 2 años ago | 2 answers | 0

Answered

Is it possible to create a program on matlab that's works on android?

Sort of https://it.mathworks.com/help/supportpkg/android/run-on-target-hardware.html?s_tid=CRUX_lftnav

Is it possible to create a program on matlab that's works on android?

Sort of https://it.mathworks.com/help/supportpkg/android/run-on-target-hardware.html?s_tid=CRUX_lftnav

alrededor de 2 años ago | 0

Answered

How to improve my code speed (for loop)

By profiling, the most computational intensive operations are x=T*(probe-ut)'; y=T*(gallery-ut)'; That calculation is inside ...

How to improve my code speed (for loop)

By profiling, the most computational intensive operations are x=T*(probe-ut)'; y=T*(gallery-ut)'; That calculation is inside ...

alrededor de 2 años ago | 0

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Answered

How to optimize only 2 variables in an objective function with 3 variables?

In this case you can set the upper and lower bound for that specific variable to the same value. Maybe it is not efficient but i...

How to optimize only 2 variables in an objective function with 3 variables?

In this case you can set the upper and lower bound for that specific variable to the same value. Maybe it is not efficient but i...

alrededor de 2 años ago | 0

Answered

How to optimize only 2 variables in an objective function with 3 variables?

Why don't you remove theta from your objective function definition and call different_function inside function? function object...

How to optimize only 2 variables in an objective function with 3 variables?

Why don't you remove theta from your objective function definition and call different_function inside function? function object...

alrededor de 2 años ago | 0

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Answered

How to change a column vector into a square a matrix?

Not as elegant as it could be but it works, especially for small matrices % matrix dimension n = 3; % your entries (here du...

How to change a column vector into a square a matrix?

Not as elegant as it could be but it works, especially for small matrices % matrix dimension n = 3; % your entries (here du...

alrededor de 2 años ago | 0

Answered

Calculate acceleration from velocity and time fron excel

acceleration = diff(data.Velocity)./diff(data.Time); Note that this vector has one entry less than the original ones, so you ma...

Calculate acceleration from velocity and time fron excel

acceleration = diff(data.Velocity)./diff(data.Time); Note that this vector has one entry less than the original ones, so you ma...

más de 2 años ago | 0

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Answered

Subscripted assignment dimension mismatch.

You can use repmat and create a char array function bigstring = string_multiplication(str,N) bigstring = repmat(str,N,1); ...

Subscripted assignment dimension mismatch.

You can use repmat and create a char array function bigstring = string_multiplication(str,N) bigstring = repmat(str,N,1); ...

más de 2 años ago | 0

Answered

Simulation errors when multiplying matrices

I start a new clean answer You don't have to use the index i inside your matrix like you are doing in your code: in that way yo...

Simulation errors when multiplying matrices

I start a new clean answer You don't have to use the index i inside your matrix like you are doing in your code: in that way yo...

más de 2 años ago | 0

Answered

Solving Complex Matrix Operations

You can do this in a for loop or using arrayfun % your A vector A = rand(1,1001); % dummy vector % calculation of the matr...

Solving Complex Matrix Operations

You can do this in a for loop or using arrayfun % your A vector A = rand(1,1001); % dummy vector % calculation of the matr...

más de 2 años ago | 0

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Answered

Replicate values in a matrix i-1 times

Quick and dirty for loop A=[1; 4; 8; 3; 2; 6] B = []; for i = 1:length(A) B = [B; repmat(A(i),i,1)]; end You can als...

Replicate values in a matrix i-1 times

Quick and dirty for loop A=[1; 4; 8; 3; 2; 6] B = []; for i = 1:length(A) B = [B; repmat(A(i),i,1)]; end You can als...

más de 2 años ago | 0

Answered

Find independent variables that minimize function

If you have only lower and upper bounds, use them directly in fmincon % your function fun = @(x) ((x(1)-real(0.5*(x(1)-(sqrt(x...

Find independent variables that minimize function

If you have only lower and upper bounds, use them directly in fmincon % your function fun = @(x) ((x(1)-real(0.5*(x(1)-(sqrt(x...

más de 2 años ago | 0

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Answered

Simulation errors when multiplying matrices

Inside the loop in the first instruction Vn(:,i) is 5x1 but T is 5x5. Matlab now (starting in 2016, I guess) implicitly expands ...

Simulation errors when multiplying matrices

Inside the loop in the first instruction Vn(:,i) is 5x1 but T is 5x5. Matlab now (starting in 2016, I guess) implicitly expands ...

más de 2 años ago | 0

Answered

Weighted fit using fmincon

How about to repeat the samples of the points you want to weight more?

Weighted fit using fmincon

How about to repeat the samples of the points you want to weight more?

más de 2 años ago | 1

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Answered

how to find the optimal value of a matrix that minimize a function?

If I understand correctly the problem can be recast to the following A*W = B*H = F; [a11 a12; a21 a22]*[w1 w2 0 0; 0 0 w3 w4] ...

how to find the optimal value of a matrix that minimize a function?

If I understand correctly the problem can be recast to the following A*W = B*H = F; [a11 a12; a21 a22]*[w1 w2 0 0; 0 0 w3 w4] ...

más de 2 años ago | 0

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Answered

plot 2 3D vectors in Matlab

% vectors a = [1 2 -3]; b = [-3 12 -13]; % starting point C0 = [0 0 0]; % put vector in a matrix, to make the code more...

plot 2 3D vectors in Matlab

% vectors a = [1 2 -3]; b = [-3 12 -13]; % starting point C0 = [0 0 0]; % put vector in a matrix, to make the code more...

más de 2 años ago | 0