Matt J
Professional Interests: medical image processing, optimization algorithms
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Intersection of two lines
You need a least squares solution, since lines in 3D do not generally intersect. Assuming your point data are in column-vector f...
약 5시간 전 | 0
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Plotting the solutions of an equation (rotated ellipsoid)
If you have the center, radii, and yaw-pitch-roll angles (in degrees) of the ellipsoid, you can plot a data-free ellipsoidalFit ...
약 5시간 전 | 0
Create a 2x3 matrix named mat_B from the first and 2nd rows, and the 2nd, 3rd and 4th columns of the matrix C.
Looks right to me.
약 13시간 전 | 0
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I dont understand why my table is displaying 1x1 sym and not a numerical value
You seem to be under the impression that vpa() converts a sym to a number. What you really want to do is use matlabFunction() to...
약 13시간 전 | 0
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How can I create a set of N diagnal matrices range from diag(1, 1, ... , 1) to diag(-1, -1, ... , -1) for testing purposes?
Do you really need all Z{i} at the same time? [C{1:4}]=ndgrid([-1,1]); C=reshape( cat(5,C{:}) ,[],4); Z=zeros(N^2,2^N); %...
1일 전 | 1
Non-linear constraints with several input variables in fmincon
Your nonlinear constraints are not differentiable. That doesn't always spell disaster, but it breaks the assumptions of fmincon....
1일 전 | 0
fsolve, fmincon producing different results
Do they both achieve the same objective value? If so, you simply have multiple solutions.
1일 전 | 0
How to extract columns from multiple 3D arrays?
Seems like you could just put them in a matrix: F=[f1(:), f2(:),f3(:),...,f7(:)]
1일 전 | 0
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How to Solve matrix equations in Matlab
With an over-determined system (3 equations and only 2 unknowns), you can't expect an exact solution. However, the solution that...
1일 전 | 1
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Efficiently assigning class property in a quadruple loop?
You've not told us the dependence of myLogicalVector and someFixedValue* on the loop variables, which is probably super-importa...
3일 전 | 0
Double Summation without using fft2 function
You can find examples of for-loop construction here, https://www.mathworks.com/help/matlab/ref/for.html#buhafgy-3
3일 전 | 0
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Sequence 1, 2, 4, 12
One possibility: p=[0.833333333333333 -4.499999999999996 8.666666666666661 -3.999999999999996]; polyval(p,1:4) polyval(...
4일 전 | 0
How to get optimal linear scaling factor for a set of vectors
I want to determine a linear scale factor for each y_raw? vector, such that the mean squared error (MSE) between the average of ...
4일 전 | 0
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Linear Equations infinite solutions parametric form
x0=pinv(A)*b; B=null(A); sol=@(c)x0+B*c;
4일 전 | 1
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제출됨
Further tools for analyzing objects in N-dimensional images
A collection of tools to supplement bwpropfilt, bwareaopen, and the like.
4일 전 | 다운로드 수: 6 |
How can I speed up (or avoid) a comparison in for loop?
You might try bwlareaopenn from this submission https://www.mathworks.com/matlabcentral/fileexchange/90762-further-tools-for-an...
4일 전 | 1
Solver based optimization passing extra parameters
nonlcon=@(x)constraintFcn(x,aa) See also, Passing Extra Parameters - MATLAB & Simulink
4일 전 | 0
How to get the file names that start with the same letter in the folder?
For example, s=dir('T*_imag.bin'); fileNames={s([s.isdir]==0).name}
4일 전 | 0
Matrix form for creation and annihilation operator with spins.
Not sure this will help, but if you can write a function that implements the operator, then his File Exchange offering, https:/...
4일 전 | 0
What should go in a next-generation MATLAB X?
My wish list: (1) Colon operator produces column vectors, not row vectors: x=1:4 (2) Optimization Toolbox solvers should ha...
4일 전 | 2
combine different size vectors into one matrix
I will assume you have the vectors in a cell array C={[2 3 4 5]; [4 7 7]; [8 8 7 4 2 5]} Then, you can simply do, z=...
4일 전 | 0
using fsolve function to solve for 2 unknowns
x0 = [80,110]; [sol, Fsol] = fsolve(@problem_one,x0), function F = problem_one(theta) theta3 = theta(1); theta4 ...
6일 전 | 1
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fminunc initial point is local minimum, but fminsearch returns reasonable estaimtes
It could happen if your objective function is piece-wise flat (and hence non-differentiable). fminsearch is a derivative-free so...
6일 전 | 0
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How can I obtain the Fourier Transformation as a product of matrices?
N = (0:255).'; X = (2*cos(((15.8*pi)/128)*N)) + (3*sin(((27.3*pi)/128)*N)); F=fft( eye(numel(X)), [],1); fX = fft(X); %...
6일 전 | 0
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Solving non linear equation "Circle" equations
Because you cannot be certain of an exact 3-way (or n-way) intersection, you need to use a numerical least squares solver like f...
6일 전 | 1
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What is the real value of "single(my_variable)"?
So the C code keeps good precission. But, does Matlab? Yes, if by "good precision" you mean up to 7 digits. You can see that ev...
6일 전 | 0
How to define a constat in function handle?
You mean like this? [a,b,c]=deal(3,4,5); f = @(x,y)a*x.^2+b*y+c Or like this? syms x y a b c f(x,y) f(x,y)=a*x.^2+b*y+...
6일 전 | 0
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Steepest descent with exact line search method
n=input("Enter the roll number:"); fobj=@(x) (x(1)-n)^2 + (x(2)-2*n)^2; gradobj=@(x)2*[(x(1)-n), (x(2)-2*n)]; x0=[1 1]; ...
6일 전 | 0
how to develope loop to save the 'n' elements from the vectors
It is not a good idea to store A(i) in separate variables. You should probably just write your equation in terms of vector opera...
6일 전 | 2
