Matt J

Last seen: ein Tag vor | Aktiv seit 2009

Followers: 14 Following: 0

Nachricht

Professional Interests: medical image processing, optimization algorithms PLEASE NOTE: I do not read email sent through my author page. Please post questions about FEX submissions in their respective Comments section.

Statistik

All

RANG
6
of 297.420

REPUTATION
31.328

BEITRÄGE
277 Fragen
12.012 Antworten

ANTWORTZUSTIMMUNG
78.34%

ERHALTENE STIMMEN
4.146

Abzeichen anzeigen

Feeds

Beantwortet
How can I create multiple function handles in a for loop?
The best would be to just have a matrix-valued function, fun=@(x) x.^2-mymat(:).*x+mymat(:) but you could make a cell array of...

etwa 16 Stunden vor | 0

Beantwortet
Filtering Blobs on a Binary Image
If you can form an under-estimate of the extent of the blobs, let's call them sub-blobs, then you can fit a Gaussian lobe to the...

etwa 19 Stunden vor | 0

Beantwortet
polyshape not closing a circle
wgs84 = wgs84Ellipsoid("nm"); lat0 = 42.3601; lon0 = -71.0589; r = 10; [lat,lon] = scircle1(lat0,lon0,r,[],wgs84); circle...

ein Tag vor | 0

Beantwortet
Why does the Code Analyzer flag this as an error?
Mathworks Support has classified it as a bug.

ein Tag vor | 1

| akzeptiert

Beantwortet
How do you change the output dimension of a NN layer?
Should I flatten the inputs and then concatenate them similar to this example? Probably. See if the attached network does what...

2 Tage vor | 0

Beantwortet
Display a small matrix as a gray scale image
T2 =[ 0.4706 0.9804 0.8392 0.3216 0.9804 0.8392 0.3216 0.4706 0.8392 0.3216 0.4706 0.9...

2 Tage vor | 0

| akzeptiert

Beantwortet
How to freeze specific neuron weights in a feedforward network during training process?
I don't think you can do it without the Deep Learning Toolbox. If you have the Deep Learning Toolbox, you can define a custom la...

3 Tage vor | 0

Beantwortet
Please help with this multiplication problem
You can multiply directly. Example: [m,n,r]=deal(3,4,2); A=rand(m,1,r); B=rand(1,n,r); C=A.*B; whos A B C

3 Tage vor | 0

| akzeptiert

Beantwortet
sub2ind() errors out with NaN inputs - handled differently since R2024a
You can get the old behavior back if you need it, Sub2Ind([ 3 5 7], [ 3 3], [2 2], [1 nan]) function out=Sub2Ind(sz,vararg...

3 Tage vor | 0

| akzeptiert

Beantwortet
Non-linear constraints format for GA using solve function
I would formulate it as, N=numel(Pos_Input_mtx); problem.Constraints.c1=abs(Pos_Input_mtx(:)-Pos_Input_mtx(:)') >= (1-eye(N)...

4 Tage vor | 0

| akzeptiert

Beantwortet
Summing function handles of multiple variables across one of the variables
Nesting function handles n-fold is going to be very inefficient, and is usually not a good idea. Usually, it is best to vectoriz...

4 Tage vor | 0

Beantwortet
Error using trainNetwork Invalid training data. For classification tasks, responses must be a vector of categorical responses. For regression tasks, responses must be a vector
Instead of using Matlab's dicePixelClassificationLayer, you can try the following custom output layer: classdef GeneralizedDice...

6 Tage vor | 0

Beantwortet
Ifft2 results do not match that of irfft2 in Pyhton
I'm not a Python user, but if rfft2 only gives you positive x-frequencies, I would imagine it also only gives you positive y-fre...

7 Tage vor | 0

Frage

Three dots at the end of a line of code
Why does one of my lines of code have three dots enclosed in a box? What does it mean? Clicking on it does nothing.

8 Tage vor | 1 Antwort | 0

1

Antwort

Beantwortet
Looking for linear system Ax=0 precision improvements
s=max(abs(A),[],1); x = null(A./s)./(s')

9 Tage vor | 0

Beantwortet
Finding x and y values of minimum z in 2-variable function.
The continuous minimum can't be at (5,2) as you claim. Direct evaluation shows that the value of z at (5.5,10) is lower. loopi...

9 Tage vor | 0

Beantwortet
Using fft and ifft with less frequencies than input points
What I would want to do, is to insert an N, f.e. N=100, but get an array 10001x1. %Grid Nx = 100; L = 10; dx = L/(Nx-1); ...

9 Tage vor | 0

Frage

Why does the Code Analyzer flag this as an error?
Why does the Code Analyzer flag this code as an error? It runs fine: try error("It's bad") catch ME warning('Error...

9 Tage vor | 2 Antworten | 0

2

Antworten

Beantwortet
How to fastly calculate this real number matrix manipulation?
e=(1:A)'; I=reshape(e,1,1,[]) == repmat( e,1,B); Xp=permute(X,[3,2,1]); D=X./(X-Xp); D(I)=1; M = ipermute( prod(D,1) ,[...

11 Tage vor | 0

Beantwortet
How to solve the error generated while defining custom FFT layer?
Your predict() method is written to expect that the input X will be a cell array. It's not clear why you expect this, but you sh...

11 Tage vor | 0

| akzeptiert

Beantwortet
How do I edit a loop to be able to store the variables and outputs used in each loop in a way which can be graphed?
D = 0.3 k = 0.0002 Rvalues = 10^4:10^5:10^8; nR=numel(Rvalues); X=nan(1,nR); for i=1:nR R=Rvalues(i); ...

11 Tage vor | 0

Beantwortet
reshape 4-dimension array
Download this File Exchange package, https://www.mathworks.com/matlabcentral/fileexchange/115340-block-transposition-permutatio...

13 Tage vor | 0

Beantwortet
Speed up this bottleneck line of code
If you can construct c in transposed form, there are some savings to be had, n = 10000; m = 5000; k = 20; a = rand(n,m);...

13 Tage vor | 0

| akzeptiert

Beantwortet
nonlinear spline fit with unknown upper bound of interpolation domain
The upper bound is way larger than the fitted parameters at x < 6, causing an extremly large curvature at x > 6 which makes the ...

17 Tage vor | 0

| akzeptiert

Beantwortet
Differentiating in one direction using FFT2
fft2(u) is equivalent to fft( fft(u,[],1) ,[],2), if that helps at all. Truthfully, it doesn't appear that you need to use fft2...

17 Tage vor | 0

| akzeptiert

Beantwortet
need to vectorize efficiently calculating only certain values in the matrix multiplication A * B, using a logical array L the size of A * B
Is v much smaller than m or n? If so, one approach might be with an outer product decomposition: L=sparse(L); %if L was not pre...

18 Tage vor | 1

Beantwortet
shared colorbar for specific plots in tiledlayout
Using nestedLayouts from the File Exchange, https://www.mathworks.com/matlabcentral/fileexchange/161736-grids-of-tiled-chart-la...

19 Tage vor | 0

Beantwortet
MATLAB Optional Function Arguments
Using the arguments block is more robust, but I'm unable to find a way to make multiple inputs independently optional. The way ...

19 Tage vor | 2

| akzeptiert

Beantwortet
Set number of rows in output variable using indexing within for loop, add variable to new table
I would like to put the two calculated variable columns directly after the variable column in the original table. And you want ...

20 Tage vor | 0

Beantwortet
What happens if the termination condition is satisfied before the constraint in matlab's fmincon?
The only time fmincon will stop without satisfying the constraints (within ConstraintTolerance) is if the MaxItertions or MaxFun...

20 Tage vor | 0

| akzeptiert

Mehr laden

Matt J

Statistik

MATLAB Answers

MATLAB Answers

Cody

Cody

File Exchange

File Exchange

Cody

Cody

Cody

Cody

Cody

MATLAB Answers

Feeds

1

2