Matt J
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.
Statistics
RANK
6
of 244.156
REPUTATION
21.290
CONTRIBUTIONS
196 Questions
8.374 Answers
ANSWER ACCEPTANCE
75.51%
VOTES RECEIVED
2.834
RANK
259 of 17.068
REPUTATION
5.253
AVERAGE RATING
4.90
CONTRIBUTIONS
33 Files
DOWNLOADS
321
ALL TIME DOWNLOADS
43891
CONTRIBUTIONS
0 Posts
CONTRIBUTIONS
0 Public Channels
AVERAGE RATING
CONTRIBUTIONS
0 Highlights
AVERAGE NO. OF LIKES
Your submission is selected as "Pick of The Week"
Awarded to Matt J on 08 Oct 2021
Your submissions were downloaded 250 or more times in a month
Awarded to Matt J on 01 Nov 2019
Publish your first review
Awarded to Matt J on 09 Oct 2019
Your submissions received 25 five star ratings
Awarded to Matt J on 09 Oct 2019
Publish your first submission
Awarded to Matt J on 09 Oct 2019
Answer 50 questions that were unanswered for more than 30 days
Awarded to Matt J on 12 Oct 2017
Contribute at least one answer each month for 36 consecutive months
Awarded to Matt J on 20 Jul 2017
Accept 50 answers given by other contributors
Awarded to Matt J on 20 Jul 2017
100 of your answers have been accepted
Awarded to Matt J on 20 Jul 2017
Provide your first answer ever to someone else's question
Awarded to Matt J on 20 Jul 2017
Content Feed
Expressing polynomial including a indefinite parameter
Possibly you mean that you want a coefficient vector as the output, rather than a polynomial in functional form. syms a x P ...
42 Minuten ago | 0
Expressing polynomial including a indefinite parameter
One way. p = @(x,a) polyval([a,-4,2-a],x); Usage: x=1; a=2; p(x,a)
etwa 5 Stunden ago | 1
Combining 3 2D graphs into a 3D figure
Something like the following, perhaps? x=linspace(0,5); z1=x.*exp(-x); z2=3*x.*exp(-4*x); Hax=axes; area(x,z1,'Parent',up...
etwa 5 Stunden ago | 0
| accepted
How can I minimize absolue value in a power optimprob?
The objective is to minimize the integral of Pgrid abs value... while the control variables are Pbatt and Pev; Ppv and Pload If...
etwa 8 Stunden ago | 0
| accepted
Finding out what initial guesses the curve fitting toolbox made for curve fit
I don't think there's anyway to dig out the initial guess generated inside fit(), but why not just specify your own random start...
etwa 23 Stunden ago | 0
| accepted
I have two arrays that I want to divide a specific way
C=A./B;
etwa 24 Stunden ago | 0
| accepted
When I export the figure, the x-axis is halved even though I have set the interval in the code.
I usually use export_fig(), https://github.com/altmany/export_fig
ein Tag ago | 0
How to fill a hollow donut-shaped object so that it looks like a circle?
load Image montage( {BW, imfill(BW,'holes')}, [],'Back','w','Bor',5)
ein Tag ago | 0
| accepted
Is there a way to set MaxSQPIter for active-set algorithm under fmincon?
Probably because you didn't pass options to fmincon. Otherwise, show us your code.
ein Tag ago | 0
histc problem in counting in particular bin
You are assuming that the bin boundaries are calculated with infinite precision, which is impossible. Likewise your data is also...
ein Tag ago | 0
| accepted
Replace value that are associated to a location by nan
spl(0<= elevation & elevation<=100)=nan;
ein Tag ago | 0
| accepted
Fit dataset to another dataset
See polyfit(). https://www.mathworks.com/help/matlab/ref/polyfit.html
ein Tag ago | 0
optimization of matrices with random initialization
Make sure your objective function code does not contain any randomization steps. Your initial guess can be random, but the objec...
ein Tag ago | 0
| accepted
HOW TO REVERSE THE BINARY IMAGES
outt33(:,:,i) = ~imbinarize( I)
ein Tag ago | 0
| accepted
What dose this function mean and what is the differentes ?
The first is calculating the number of zeros in B and the second is summing all values in B (times -1).
ein Tag ago | 0
Error in lsqcurvefit with 3 unknown parameters involved
If your model has 3 unknown parameters, then your initial guess P40 must be a vector of length 3.
ein Tag ago | 0
| accepted
sum only consecutive 1's in matrix
See, Tools for Processing Consecutive Repetitions in Vectors https://www.mathworks.com/matlabcentral/fileexchange/78008-tools...
ein Tag ago | 0
what is the fastest appproach to solve a system of non linear equations ?
Seems like it would make sense to regard this as a system of 100K simultaneous equations and solve for the PDE parameter with ls...
2 Tage ago | 0
How do we allocate equidistant points on a sinusoidal curve?
You should also have a look at interparc() https://www.mathworks.com/matlabcentral/fileexchange/34874-interparc?s_tid=srchtitle...
2 Tage ago | 0
How do we allocate equidistant points on a sinusoidal curve?
You can use fzero, x_p=0; y=@(x) -25*sin((2*pi/50)*x); fun=@(d) d.^4+( y(x_p+d^2)-y(x_p)).^2 - 0.004^2; x=x_p+fzero(fu...
2 Tage ago | 1
| accepted
drawrectangle draws rectangle even though the mouse is clicked outside the parent UIAxes
You can fall back to imrect, if necessary fcn = makeConstrainToRectFcn('imrect',get(gca,'XLim'),get(gca,'YLim')); h=imrect('Po...
2 Tage ago | 0
Array processing using Taylor Series and FOR Loops to approximate sin value for each element in that array.
The array can be of any type and dimensions. If so, why does your code assume it will be 2D? Can't it be 3D or 4D? In any case...
3 Tage ago | 0
| accepted
How to store iterative information to a matrix?
The following is pretty typical. result=nan(big_number,1); while abs(y)>=small_number &iteration<big_number [x,y] = some...
3 Tage ago | 0
how to generate points inside a rectangle not parallel to axis in Matlab
You mean you want to generate N random points? If so, then, xy=Q*([length;width].*(rand(2,N)-0.5)) + center(:)
3 Tage ago | 0
| accepted
How do I add zero padding to this convolution?
Not sure what the question is, but you can easily compare your result to direct convolution to see if it's correct. x1x2_conv =...
4 Tage ago | 1
How to tell an multi-output anonymous function to vectorize its output components which are constant
One way, f=@(x,y) completeRows({x+y;2;x*y;x.^2-1;3}); f([1 2],3) function out=completeRows(C) n=max(cellfun('length',...
5 Tage ago | 0
| accepted
Area between three curves
A=Einspeiseanteil; B=GabelstaplerP; C=max(A,B); area=trapz(X,(C-Y).*(C>=Y))
5 Tage ago | 0
How to plot vectors exactly on the edge of another graph?
t=linspace(0,360,91); t(end)=0; u=cosd(t); v=sind(t); fimplicit(@(a,b) a.^2+b.^2-1);hold on quiver(u,v,u,v,'Color','r...
6 Tage ago | 1
| accepted
