Answered
Use Indexing for more than 1 dimension of array simultaneously
Yet another way using linear indexing (showing what sub2ind( ) does internally): matrix = rand(10, 3); idx = [1; 2; 2; 3; 1; 2...

1 year ago | 0

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Indexing and turning into column vector
Not really. It's going to be a two-step process no matter how you do it (without resorting to a mex routine, which isn't worth i...

1 year ago | 0

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how to make a single array out of 2 arrays
Just use indexing. E.g., odd=[0.4357, 0.78208,0.6245] even=[0.48004,1.29188,1.54668,0.82376] both(1:2:5) = odd both(2:2:8) =...

1 year ago | 0

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Answered
Difference between 2 orientations
I would do your method #3 involving quaternions. This would give you the "smallest" rotation between the two attitudes. But you ...

1 year ago | 2

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Implicit casting overhead from real to complex when multiplying two matrices
This is not a natively supported operation (to use your terms). Yes, the real matrix must be first upconverted to a complex matr...

1 year ago | 1

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why do we initialize any vector or matrices with zero.
If you know you will be filling in the variable elements downstream anyway, it would be faster to just allocate the memory and n...

1 year ago | 0

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Complex matrix multiplication with pagemtimes
This really has nothing to do with the maturity of MATLAB ... every language that uses BLAS routines in the background will have...

1 year ago | 2

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Answered
Matrix power vs for loop
Note that the A^endtime method is probably going to be more accurate as endtime gets larger. The loop method can have a tendancy...

1 year ago | 0

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error: matrix dimensions must agree
I would presume you may need element-wise operators. Try this: func = @(K_a,freq)(-K_a./(tan(2*pi*freq*h.*(1 + 0.19./((K_a/60 +...

1 year ago | 0

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Average every 3 rows of 1 column in a 12 x 8 array
E.g., Data = [ 34 6 4 -6.60874766440390 -40.7725049965035 16217 0.289000000000000 1.02200000000000 35 6 5 -6.54326464...

1 year ago | 0

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Answered
Converting 2D cell array to 3D matrix
E.g., MyCell = repmat({(1:4)'},2,3) % small sample data [m,n] = size(MyCell); reshape(cell2mat(MyCell(:)').',m,n,[]) size(an...

1 year ago | 1

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Answered
How can I calculate the "Median" of floating point numbers
E.g., x = randi(10,2,3) y = randi(10,2,3) z = randi(10,2,3) xyz = cat(3,x,y,z) result = median(xyz,3)

1 year ago | 0

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Answered
transposing 3d matrix with permute function
MATLAB does not store trailing singleton (1) dimensions beyond the 2nd dimension. Once you permute that 1 into the 3rd dimension...

1 year ago | 2

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Scalar structure required for this assignment.
This? [Sis.On] = D_{:,2};

1 year ago | 0

Question

LU decomposition algorithm change
For this particular example: A=[ 1 2 3; 4 5 6; 7 8 9; 10 11 12]; I get two different results depending on...

1 year ago | 2 answers | 0

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Inserting a double to a cell
E.g., x = randi(100,10,10) % sample data columns = [4,7]; % columns to check minx = min(x(:,columns)) % minimum of the two co...

1 year ago | 0

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Answered
Using Matlab to solve 1D Schrödinger Equation (Strange Eigenfunctions)
Python: return is misspelled retrun The mL2V( ) function returns 1000*(y-1/2)**2 I don't see where y is defined prior to the ...

1 year ago | 0

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1×0 empty double row vector using find
Welcome to the world of floating point arithmetic. For your specific example, they are not equal. E.g., x=[0 0.1 0.2 0.3 0.4 0....

1 year ago | 1

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How to plot the first derivative of solution?
After the ode45( ) call, simply pass your x solution through your derivative function to obtain the xdot values. You can either ...

1 year ago | 0

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optimizing: fastest way to detect if ANY points are within distance N of points?
Here is a naive brute force mex routine you can try out. It makes no attempts at cache optimization or multi-threading, and is p...

1 year ago | 0

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"roots" call is not providing the correct answer
Rename your old roots file (preferred method) or move it to a directory that is not on the MATLAB path. That way it won't shadow...

1 year ago | 1

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How can ı solve this error ??Unable to perform assignment because the size of the left side is 1-by-5 and the size of the right side is 26-by-1.
You could expand the size of the LHS array. E.g., poles_real(i, 1:numel(roots_poly)) = real(roots_poly); poles_imag(i,...

1 year ago | 0

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angle of a vector centered at a certain point
Once you have the vectors, you can calculate the angles between the vectors using the technique I posted here: https://www.math...

1 year ago | 0

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How to expand dimension of a 2D array
All MATLAB trailing singleton (1) dimensions beyond the 2nd dimension are not physically stored, and will not show up in a size(...

1 year ago | 2

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A single precision matrix multiplication problem
Somewhat related side comments: In general, the BLAS/LAPACK libraries do not contain mixed type argument routines. E.g., there ...

1 year ago | 2

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How is this even logical?
When assigning into rows or columns via indexing, MATLAB will conform a RHS vector from row or column to row or column if necess...

1 year ago | 0

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Matlab crashes when running a specific Fortan MEX file under MacOS
The MATLAB Fortran API interface needs to be treated as a pass-by-reference interface. That means you need to have the exact typ...

1 year ago | 0

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What does [n==0] means?
Try it out and see: n = 3; N = 3; n == 0 n == N n = randi(4,1,10) - 1 n == 0 n == N Returns logical true/false where val...

1 year ago | 0

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How to update a symmetric matrix?
E.g., M = rand(6)<0.3; M = double(logical(M+M')) % an arbitrary symmetric matrix VarMin= 1; % Lower Bound of Variables...

1 year ago | 0

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Answered
Recursive Method returning answers backwards
This is a very convoluted way to program the Euler method. There is no need for recursion here, just use simple loops instead. ...

1 year ago | 1

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