In addition to what @Image Analyst has written, I would advise turning this into a function with p1, p2, p3 as input arguments a...

4 mois ago | 0

Difference between using single quotes ('xyz') and double quotes ("xyz") in formatspec
In MATLAB, single quotes ' ' are used to create char type variables, and double quotes " " are used to create string type variab...

4 mois ago | 0

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Error in ode45 while doing numerical integration
The function handle you pass to ode45( ) needs to have a (t,y) signature. E.g., [t,y] = ode45(@(t,y) myode(t,gt,g), tspan, ic, ...

4 mois ago | 0

How to multiply higher order matrices?
You may need to permute your arrays first to get your desired 2D slices in the first two dimensions. A = whatever B = whatever...

4 mois ago | 2

Using matrix to index another matrix?
Does this do what you want: x = sub2ind(size(B),(1:size(A,1))',A(:,1),A(:,2),A(:,3)); Output = B(x);

4 mois ago | 0

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Equivalent of c++'s NULL or python' s None in MATLAB
This will probably depend on how these are used downstream in your code and whether you have arrays of them to deal with. If th...

4 mois ago | 1

X Y Z angles of a D20 (icosahedron) for gravity projection
If you have the 3D normal vectors, then all you need to do is take the dot product between them and the "flat" face normal vecto...

4 mois ago | 1

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modify a row of an array within a function
This can sometimes be done inplace depending on how you write the function and how you call the function. One requirement is yo...

4 mois ago | 0

Operator '-' is not supported for operands of type 'function_handle'.
You are using u as both an input argument and a global function handle function A3 = odeFun(t, u) <-- input argument global R...

4 mois ago | 0

Solve a system of 3 second order ODE
You will need to change your scalar equations to vector equations, and you will need to change your derivative function to a vec...

4 mois ago | 0

Need to speed up the generation of random numbers.
You could over generate a large matrix and then pick off the number of elements you need later. E.g., C = rand([5 size(A)]); T...

4 mois ago | 0

How do i create a large matrix with a formula?
N = 1000; a = 2 * pi * f * T * (0:N-1)'; x = [cos(a) -sin(a)];

4 mois ago | 1

Matrix multiplication to get covariance matrix
@Tintin Milou MATLAB variables do not have a "symmetric" attribute flag that I know of. Just because you create a variable that...

4 mois ago | 0

Why can't complex integer arithmetic be done?
I think the main reason for disallowing integer array arithmetic in MATLAB is because of the ambiguity caused by the max(min( ))...

4 mois ago | 1

How can I split C/C++ Code in multiple files and still use MEX
Use the -c option to compile the B and C stuff to produce only object files without any linking: mex -c B.c C.c Then compile y...

5 mois ago | 1

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Matrix multiplication. Trying to get scalar solution
Those should be matrix multiples, not element-wise multiplies. Remove the dots. E.g., top=nMode * M * u0; bot=nMode * M * nM...

5 mois ago | 0

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Adapt RK4 ODE Solver from first order to 2nd order
Try this for starters yt = zeros(numel(y0),length(h:tfinal)); %Memory Allocation And then maybe this is what is intended for i...

5 mois ago | 0

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Error using vertcat Dimensions of arrays being concatenated are not consistent.
You have a mismatch in the number of arguments. E.g., this [V,y] = ode45(@(~,y) fun(del_h1,del_cp1,cp1),Vspan,y0); should be ...

5 mois ago | 0

Replacing matrix n column values
E.g., temp = A(:,70:80); temp(temp<0) = 0; A(:,70:80) = temp;

5 mois ago | 1

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Solving an overdetermined system of linear equations
Since you can simply plug in those values to verify that they satisfy all four equations, the conclusion would be that you have ...

5 mois ago | 0

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How to create a cell array with binary numbers?
Your pop variable has 1000x11 = 11000 elements. Your for-loop only assigns values to 1000 of those elements (the first column)....

5 mois ago | 0

Vector sum of forces
sqrt(sum(F.*F,2))

5 mois ago | 0

invalid use of operator
You are missing a ( after the second "if", and you are missing an "end" statement. That being said, my suggestion would be to u...

5 mois ago | 0

Need Help Solving Two Coupled ODEs
The derivative function needs to have the input arguments specified. In your current code above, you have no inputs specified. ...

5 mois ago | 0

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Versions of Euler Methods
methodA has a fundamental flaw: y(i+1) = y(i)+ h*func( t(i) + h/2, (y(i)+y(i+1))/2 ); You can't use y(i+1) on the right hand s...

5 mois ago | 1

Problem with matrix differential equation resolve in Matlab with ode45
Normally I would have expected ode45( ) to pass q as a 4x1 column vector. Also, I don't see anything in your code solving for q...

5 mois ago | 0

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Question regarding quaternion conventions; particularly with respect to point vs frame rotations

5 mois ago | 0

Using vectorization to shorten run time
E.g., [P,D] = meshgrid(p,d); % generate all possible combinations X = [P(:) D(:)]; % combine them into side-by-side column vec...

5 mois ago | 1

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why does dimension of input variable change in ode45
The dimension changes to a column vector because that is the way ode45( ) operates. Your derivative function needs to be able t...

5 mois ago | 1

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Maatlab crash with .mex function
I had to make some assumptions about how the matrix data areas are supposed to be loaded. We can try this first to see if these...

5 mois ago | 0