polyfit step by step or analytics
polyfit is the mfile you can step through in debugging mode. If you call with one outout argument (non normalized) it build van...

2 months ago | 0

Inserting 0 in sparse matrices without changing sparsity pattern?
Is it possible to tell MATLAB to not change the sparse matrix, but instead treat inserted zeros as any other value? Short answ...

2 months ago | 1

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How to fix my linear fit model?
Assuming you know where to split the data for left and right lines: x = [0 1 2 3 4 5 6 7 8 10 11 12 13 14 15 16 17 18 19 20 ......

2 months ago | 1

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How to fix my linear fit model?
This returns the piecewise linear function that is continuous at the break point. The correct break point is close to 18.6054 a...

2 months ago | 1

strcmp gives a 0 while it should be a 1
Look more carefully: There is a 'c' before '49' in A but not in B

2 months ago | 0

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Basic FFT Question: What range to sample the function in.
" However I am under the impression that the fft should not be sensitive to this change. " Your expectation in incorrect When y...

2 months ago | 0

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getfield to get values from an entire struct array?
Create 1 x 3 struct array with field named 'afield' s = struct('afield', {11 12 13}) s(1) s(2) s(3) % Here is the command t...

2 months ago | 0

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express basis spline derivative in terms of interpolation values
x = [1 2 3 4 5]; y = randn(size(x)); k = 5; f = spapi(k,x,y); B = spapi(k,x,eye(length(x))); fdd = fnder(f, 2); Bdd = ...

2 months ago | 0

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Use MATLAB Coder to convert matlab code to mex without using multi-threading
https://www.mathworks.com/help/coder/ug/use-parallel-for-loops.html

2 months ago | 0

How to get all possible combination With the total number of possible combination for "n" variables that can take different values

2 months ago | 0

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Possible issues with solving iterative linear systems with mldivide
"Is there a way to see the matrix solver steps to see which expressions might have an issue?" No they are LAPACK/BLAS based cod...

2 months ago | 0

Sparse matrix vector product returns null.
"What can cause this issue?" Nothing. What you claim likely would not happen. Unless if you show an example.

2 months ago | 0

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How to define if/else non linear constraint in an optimization problem
Simply solve three different optimization pbs with the three repectively constraints independently and ignore the two other, the...

2 months ago | 1

How to use loop to fill in specific numbers?
T = combinations(1:4,1:8) % for alder release that does not support combinations [v1 v2] = meshgrid(1:4,1:8); v1 = v1(:); ...

2 months ago | 0

Error With Least Squares Approximation
Few other recommendations beside what Torsen and John altrady told you: Lower the polynomial order, do not go above 7, But you ...

2 months ago | 0

Question

ANY and ALL with NaN array
According to any documentation page, it " determines if any element is a nonzero number". OK to me NaN is nonzero number so I do...

2 months ago | 1 answer | 0

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Make histogram from multiple cells.
% Generate dummy test data C=arrayfun(@(varargin)randn(5+randi(20),24), 1:30, 'unif', 0); A=cell2mat(C(:)); % m x 24, like c...

2 months ago | 0

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My First Derivative is not correctly calculated in matlab
syms yApprox(X1) a0 a1 a2 a3 a4 a5 a6 yApprox = a0 + a1.*X1 + a2.*(X1).^2 + a3.*(X1).^3+ a4.*(X1).^4 + a5.*(X1).^5 + a6.*(X1).^...

2 months ago | 0

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for loop vectorization of De Boor algorithm
Old question, but I'll reply it for future readers that wonder how to tackle the same problem. I did a quick and dirdty vectori...

2 months ago | 0

Increase plot speed in MATLAB
Try to look at animatedline command Also look at drawnow with or without limitedrate option, it somewhat has certain effect, ev...

2 months ago | 0

Error calculating inverse for matrix block of LU decomposition of a full row rank matrix
It's a little bit perturbant, but reading the lu doc I don't see why U1 must have the same rank than U (or A, meaning 100 on you...

2 months ago | 0

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de boor bspline algorithm
A very late answer, but as I deal myself with de Boor algorithm I look what exists out there. If the question concerns the 3D a...

2 months ago | 0

For a repeated eigenvalue only one eigenvctor is being returned
Indeed in case of eigenvalue with multiplicity > 1; the problemie is numerical challenging and MATLAB might fail to find the cor...

2 months ago | 0

How "chol" and "qz" MATLAB algorithms are utilised in the "eig" MATLAB function?
See stage 3 described in https://netlib.org/lapack/lug/node56.html or somewhere in this file

2 months ago | 0

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steps to convert spline from B-form to pp-form (fn2fm)
The pp-form stores the polynomial of each each subiterval, the variable is x := (t-ti) where ti is the left knot of interval #i....

2 months ago | 0

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How to extract a matrix of values from cell array of cell arrays of structs
Generate data (Thanks Voss) n1 = 3; n2 = 4; mse = cell(1,n1); for ii = 1:n1 mse{ii} = cell(1,n2); % row vector for...

3 months ago | 0

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Where is dlfeval tracing information stored?
I don't kwow the dlarray class but IMO it looks like the creating function handle f is stored in some sort of private property i...

3 months ago | 0

Question

Default rank revealing tolerance
In few MATLAB functions such as RANK, PINV, ORTH there is a parameter TOL. MATLAB uses the default value as % tol = max(size(A...

3 months ago | 0 answers | 1