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How can I stabilize the matrix left division (i.e. "\")?
Try pinv, lsqminnorm it can stabilize somewhat the inversion with (near) singular matrix. Both bave a tolerance argument to tune...

mehr als 2 Jahre vor | 0

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square matrix containing Chebyshev polynomials becomes singular when its size becomes greater than a certain value
That is exactky what I have suggested in my answer: use the Chebyschev nodes t0 = 0; tf = 4; N = 75; syms x h = chebyshevT(...

mehr als 2 Jahre vor | 0

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square matrix containing Chebyshev polynomials becomes singular when its size becomes greater than a certain value
If you select discrete points d the Chebychev nodes see definition wiki, and not uniform, it will become well posed.

mehr als 2 Jahre vor | 0

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interpolate a 2D map (array) of density samples and preserve the total ?
Use trapz for the integration (not sum), it should match (up to round off) with linear interpolation and interger subsamping fo...

mehr als 2 Jahre vor | 0

Frage

xlabel/ylabel 'HorizontalAlignment' issue
I don't understand the 'HorizontalAlignment' of the text labels. It is not centered (when the figure has different size than the...

mehr als 2 Jahre vor | 1 Antwort | 2

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Coefficents of piecewise polynomial in matlab
Similar answer as here points = [1 0 -1 0 1;0 1 0 -1 0]; pp = cscvn(points) m = pp.dim; p = pp.pieces; %D = diff(poi...

mehr als 2 Jahre vor | 0

Beantwortet
cscvn of a function, coefficients and breaks
This is how to use pp m = 2; n = 5; % 25 in the original question points = rand(m,n); pp = cscvn(points) m = pp.dim; p =...

mehr als 2 Jahre vor | 0

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How to index two vectors together
There is FEX, and fast if you have compiler and compile the mex file. https://www.mathworks.com/matlabcentral/fileexchange/2985...

mehr als 2 Jahre vor | 0

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The difference between performing the fft2 and the convolution
Use this function, it will perform the convolution using fft method rightly https://www.mathworks.com/matlabcentral/fileexchang...

mehr als 2 Jahre vor | 0

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How can I rotate the axes' labels parallel to the orientation of the axes?
Try this (the letters of label are rotated but the aspect ratio remain constant so they can be read easily but are not look like...

mehr als 2 Jahre vor | 0

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Compact way to calculate the centroid of a boundary of a set of points
@Sim The area of the polygonal (A in the book) is sum(A)/2 in Jan code. So sum(A)*3 in Jan's code is equal to 6*area. They are...

mehr als 2 Jahre vor | 0

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Mex function Implementation for nested-functions
you did not include operation.c in mex command

mehr als 2 Jahre vor | 2

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Beantwortet
Strange warning how to interpret it?
Fixed with update 4 https://www.mathworks.com/support/bugreports/3114312

mehr als 2 Jahre vor | 2

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Beantwortet
Compute only a few entries of a big matrix product
It will not store the result in 2D matrix but 3D array. I hope you can switch to this format of storage. x=rand(10000,10); k =...

mehr als 2 Jahre vor | 0

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Matrix addition only to elements equal to zero
C=B; B0 = B==0; C(B0)=A(B0);

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Code gets stuck loading when I try to run it.
First look of your code shows that you do this mistake: https://www.mathworks.com/help/matlab/matlab_prog/preallocating-arrays....

mehr als 2 Jahre vor | 0

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How to efficiently calculate a weighted sum of 3 dimensional matrix through a vector in matlab
This uses matrix multiplication so it should be well optimized and fast. [m,n] = size(A, [1 2]); C = reshape(A,m*n, []) * B(:)...

mehr als 2 Jahre vor | 2

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Beantwortet
Matrix inverse in objective function
The inv() is not supported by optimization expression see https://www.mathworks.com/help/optim/ug/supported-operations-on-optimi...

mehr als 2 Jahre vor | 0

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Beantwortet
Find all possible combinations of numbers with a specific array length
char(dec2base(0:4^12-1,4)+('A'-'0'))

mehr als 2 Jahre vor | 1

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Order of code execution seems weird
%% Function in app.PlotSetup function printProcess(app, message) app.StatusEditField.BackgroundColor = app.yellow; app.Status...

mehr als 2 Jahre vor | 1

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how to use plot to draw a minor arc in matlab without calculating the angle range?
% Generate A, B, C, C is the center and A B are two points on circle r = rand(); C = randn(2,1); phi1 = 2*pi*rand; A = C + r...

mehr als 2 Jahre vor | 1

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Multipilication of N-dimension array
D = rand(3, 3, 3); rotm1 = rand(3, 3, 2); for num=1:size(rotm1,3) for i=1:size(D,3) res(:,:,i,num)=rotm1(:,:...

mehr als 2 Jahre vor | 1

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Why does C{1}(1) work but C(1){1} results in an invalid array index error in MATLAB?
"I would like to understand the rationale behind MATLAB's requirement for parentheses indexing to appear last in an indexing exp...

mehr als 2 Jahre vor | 0

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How can I produce this matrix?
m=6 n=3 j=randperm(m,n-1); A=accumarray([2:n;j]',1,[n,m]); A(1,setdiff(1:end,j))=1

mehr als 2 Jahre vor | 1

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Implicit expansion for griddedInterpolant
You can do your own extension as showed here https://www.mathworks.com/matlabcentral/answers/2043017-bilinear-interpolation-fas...

mehr als 2 Jahre vor | 0

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Linking Matlab Libraries to Mingw for Another C++ Program
You need https://www.mathworks.com/products/matlab-compiler-sdk.html

mehr als 2 Jahre vor | 0

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matrix value propagation along the rows
Any of these should do A = [1 2 3 4 5 6 7] B(1:19,1:7)=repmat(A,19,1) B(1:19,1:7)=repelem(A,19,1) B(1:19,1:7)=A(ones(1...

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Bilinear interpolation faster than interp2?
Try this, about 5 time faster for your example clc close all n = 7; nq = 30; curv = 2.5; %qinterp2 works properly only if c...

mehr als 2 Jahre vor | 1

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adding all fields of a structures
s.bin_1=array2table(rand(2,3)); s.bin_2=array2table(rand(3,3)); s.bin_3=array2table(rand(4,3)); c=struct2cell(s); newstruc...

mehr als 2 Jahre vor | 0

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How to calculate the computational complexity of filtfilt low-pass filter?
filtfilt just do twice (forward + backward) the filter. In your case it is IIR, where the complexity is O((length(a)+length(b))...

mehr als 2 Jahre vor | 0

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