Submitted

Multiple eigen-values for 2x2 and 3x3 matrices
Compute in one shot the eigen-values of multiples (3 x 3) matrices using Cardan's formula

Submitted

MultipleQR
Perform a bunch of QR factorization of same size matrix

How to put a spline through points representing a path
Put this next-below to your code waypoints=unique(waypoints,'rows','stable'); % <- this is required because your example as dup...

17 días ago | 1

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Extract first and last nonzero elemenents inside subarrays avoiding mat2cell
A = [0 0 1 2 0 5 0 0 6 0 3 0 ; 0 3 0 2 6 0 0 0 0 0 0 0]; b = reshape(A.',6,[]) ~= 0; [m,n] = size(b); [~,istart] = max(b,[]...

19 días ago | 0

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how to generate permutations of N numbers in K positions
No loop, no extrenal file needed N=5; K=3; P=nchoosek(1:N,K); P=reshape(P(:,perms(1:K)),[],K) You might further sort the p...

19 días ago | 1

How to generate this matrix?
>> rho=rand rho = 0.8832 >> N=4 N = 4 >> a=rho.^(0:N-1); >> M=toeplitz(a,a) M = 1.0000 ...

20 días ago | 0

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Roots of a sixth order polynomial in symbolic form
"Ok let me elaborate a bit further. I have a system with a sixth order denominator polynomial, like i mentioned in the question....

22 días ago | 0

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How to vectorize A\B operation on slices of 3D matrices?
Yes there is new news since I post this MultipleQR fex (MEX required, OpenMP multithreading), for 6 x 6 this is the speed up on ...

23 días ago | 1

Determine polynomial coefficients so that it's roots lie on the unit circle
For P(z) = a*z^2 + b*z + c; I claim this is these two conditions are equivalent to the fact that P has two roots on unit circ...

25 días ago | 1

Why not use object oriented programing? Put your external parameters in properties. Put your functions as methods. Implement an...

alrededor de 1 mes ago | 0

Piecewise differentiation, automatic identification of pieces

alrededor de 1 mes ago | 2

Submitted

Random derangement
Generate sequences of random derangement

Why Contour matrix M ( [M,c] = contour(__) ) contains the data points exceeding xmax/ymax?
[M,h]=contourf(f,8) Return contours of 8 levels, not single level of value 8. You might use this function to decode the output...

alrededor de 1 mes ago | 0

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What frustrates you about MATLAB? #2
Some time data comes as single, but text just rejects it >> x=single(0); >> y=single(0); >> text(x,y,'Why single is not suppo...

alrededor de 1 mes ago | 1

How can I get randperm to return a permutation of a vector that has no entries at their original positions?
Here is an implementation of a non-rejection method and unbiased random derangement: function p = randder(n) % p = randder(n) ...

alrededor de 1 mes ago | 2

matrix in special arrangment for cycler gemetry
>> A=[11 12 13 14 15] A = 11 12 13 14 15 >> toeplitz(A,A) ans = 11 12 13 14 15 ...

alrededor de 1 mes ago | 0

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how matlab stores graphics objects?
All graphic objects are class "handle". Handles is a identify to designate the object and it's obviously 8 bytes as showed by wh...

alrededor de 1 mes ago | 0

speeding up my for loop
function y=divisors2(N) f = factor(N); [~,~,J] = unique(f); n = accumarray(J,1); y = prod(n+1); end Test >> N=27022021 ...

alrededor de 1 mes ago | 1

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Check if nullspace is contained in another + finding intersection of 2 nullspaces.
First question: KA = null(A); KB = null(B); % Check span KA is included in span KB PKA = KB*(KB'*KA); % Projection KA on ...

alrededor de 1 mes ago | 1

How can I get randperm to return a permutation of a vector that has no entries at their original positions?
This will do what you ask for https://www.mathworks.com/matlabcentral/fileexchange/30189-randpermfull?s_tid=srchtitle Even bet...

alrededor de 1 mes ago | 0

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Theory of Bicubic interpolation

alrededor de 2 meses ago | 0

Submitted

Free-knot spline approximation
Least squares approximation of 1D data using free-knots spline

Finding LAT LONG inside a circle of a given LAT LONG .
% Random data lonA=rand*360; latA=rand*180-90; n = 10000; lonP=rand(1,n)*360; latP=rand(1,n)*180-90; earthradius = 6357;...

alrededor de 2 meses ago | 0

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HELP. Need to understand MATH behind scatteredInterpolant or Interp2 function
"Based on the equation that I had in that screen shot would you assume that the other model is using a simplified linear interpo...

alrededor de 2 meses ago | 0

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How to generate a nearly symmetric matrix?
Just generate first a symettric matrix then perturb a "the overwhelming minority" of elements. Whatever that definnition means....

alrededor de 2 meses ago | 1

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HELP. Need to understand MATH behind scatteredInterpolant or Interp2 function
Run this, that show the "formula" and how to get zq = -38.5561 zq_check = -38.5561 Code to check 'linear' met...

alrededor de 2 meses ago | 0

In a vector, how to remove neighbours too close from one another
Using stock function >> uniquetol([1 6 12 17 23 25 34],10,'DataScale',1) ans = 1 12 23 34 Jan's various ...

alrededor de 2 meses ago | 2

Generate random integers that sums to a specific number within a specific range
Unfortunately the uniform distribution with bounds for integer is much more challenging. One way is to approximate by rounding t...

alrededor de 2 meses ago | 0

How to calculate the pairwise distince between two dataset without any loop
If you have latest MATLAB release (for pagemtimes) and download this Multiple same size solver FEX X = [1 2 1;3 4 2;5 6 3] Y =...

2 meses ago | 0

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