Risposto
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...

oltre 2 anni fa | 2

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Risposto
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...

oltre 2 anni fa | 0

Risposto
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 +...

oltre 2 anni fa | 0

Risposto
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...

oltre 2 anni fa | 0

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Risposto
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...

oltre 2 anni fa | 1

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Risposto
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)

oltre 2 anni fa | 0

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Risposto
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...

oltre 2 anni fa | 2

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

oltre 2 anni fa | 0

Domanda

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...

oltre 2 anni fa | 2 risposte | 0

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risposte

Risposto
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...

oltre 2 anni fa | 0

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Risposto
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 ...

oltre 2 anni fa | 0

Risposto
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....

oltre 2 anni fa | 1

Risposto
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 ...

oltre 2 anni fa | 0

Risposto
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...

oltre 2 anni fa | 0

Risposto
"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...

oltre 2 anni fa | 1

Risposto
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,...

oltre 2 anni fa | 0

Risposto
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...

oltre 2 anni fa | 0

Risposto
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(...

oltre 2 anni fa | 2

Risposto
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 ...

oltre 2 anni fa | 2

Risposto
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...

oltre 2 anni fa | 0

Risposto
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...

oltre 2 anni fa | 0

Risposto
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...

oltre 2 anni fa | 0

Risposto
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...

quasi 3 anni fa | 0

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Risposto
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. ...

quasi 3 anni fa | 1

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Risposto
How to randomize order of functions
E.g., Using the cell array approach with randperm: function [results] = runTests(testparameters) f = {@test1,@test2,@test3,@te...

quasi 3 anni fa | 0

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Risposto
eval() is too slow to numerically evaluate a function with X(t) and Y(t).
Something like this? syms X(t) Y(t) Vfun = [2*X + Y ; cos(X)*X^2 + Y^3 ; 3 + sin(Y)] syms x y vfun = subs(Vfun,[X Y],[x y])...

quasi 3 anni fa | 0

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Risposto
I have one column data 57600 points, how can i convert it to 240 by 240 matrix!
x = your column vector result = reshape(x,240,240); or you might need the transpose: result = reshape(x,240,240).';

quasi 3 anni fa | 0

Risposto
I want to calculate pi^2 to 22 decimal places
You can use this excellent FEX submission by John D'Errico: https://www.mathworks.com/matlabcentral/fileexchange/36534-hpf-a-bi...

quasi 3 anni fa | 2

Risposto
How to stop running code once conditions are met?
If your Birthday function is supposed to represent only one trial (a reasonable thing to do), then you should be returning n, no...

quasi 3 anni fa | 0

Risposto
How to fix the must be a column vector error?
You should double check your derivative function. Shouldn't the result be a 4-element column vector that is a function of q? Ne...

quasi 3 anni fa | 0