Community Profile

photo

Matt J


Last seen: Today Active since 2009

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

All
  • Grand Master
  • Most Accepted 2021
  • Editor's Pick
  • Personal Best Downloads Level 4
  • First Review
  • 5-Star Galaxy Level 5
  • First Submission
  • Revival Level 4
  • 36 Month Streak
  • Thankful Level 5
  • Knowledgeable Level 5
  • First Answer

View badges

Content Feed

Answered
Efficient way of Vectorization
Unfortunately, this is a situation where the for loop is the fastest option. This is because vectorized solution does much more ...

7 hours ago | 1

| accepted

Answered
how extract two arrays in matlab of unequal length
Yes interp1 to sample the curves at corresponding points. Then you can subtract them freely.

7 hours ago | 0

| accepted

Answered
initial point is a local minimum. Optimization completed because the size of the gradient at the initial point is less than the default value of the function tolerance.
I suspect your FiniteDifferenceStepSize is too small. Be mindful of the guidelines for Optimizing Differential Equations.

14 hours ago | 0

Answered
Parameters seem to not be optimizing in fmincon
If the exitflag says a minimum was found then there is probably nothing suspect about the solution or the way it was reached. Th...

14 hours ago | 0

Answered
defining state matrix as anonymous function
For example B = @(I1,L)[0 0 1/(I1) 0 0 0 0 0 0 -1/L]; B(2,1)

1 day ago | 0

Answered
How to save multiple matrices in each iteration of a for loop into a structure?
clear S for k = nLevels:-1:1 S(k).subband = pyrBand(pyrRef, pind, k); S(k).rx = conv2(subband(k),kernelx); S(k)....

1 day ago | 0

| accepted

Answered
Error in interpolating: Actual data does not match with interpolated data
load inputData i=11; j=3; %query points (Lat and Alt) %% interpolate LUT1=griddedInterpolant(Long1c_4d,Lat1c_4d,Alt1c_4...

1 day ago | 1

| accepted

Answered
How to close boundary of a circular object in binary image
load Image [c,r]=imfindcircles(BW,[10,100]); area=pi*r^2

1 day ago | 0

Answered
How to find and fit the objective function for a damped oscillation?
Using fminspleas from the File Exchange, https://www.mathworks.com/matlabcentral/fileexchange/10093-fminspleas [t,F]= readvar...

2 days ago | 1

Answered
interpolation of a structure array
fcn=@(f)interp1(f, linspace(1,numel(f),101) ); for i=1:numel(TrajXLstance) TrajXLstance(i) = structfun(fcn, TrajXLs...

2 days ago | 0

| accepted

Answered
Finding min and max values in a structure
each field consisting of a cell of numbers If you really do mean a cell array, that seems like an inadvisable organization of t...

2 days ago | 0

Answered
Type conversion happens before matlab Set method is called in classes, problem with setting int64(Nan) = [] default is 0
Another approach, using subsasgn(). This one avoids conversion of obj.a to double. >> obj=myclass; obj.a=1:5, obj.a(2)=nan o...

2 days ago | 1

Answered
Type conversion happens before matlab Set method is called in classes, problem with setting int64(Nan) = [] default is 0
One possibility: >> obj=myclass; obj.a=1:5, obj.a(2)=nan obj = myclass with properties: a: [1 2 3 4 5] obj...

2 days ago | 1

Answered
How do I interprete Camera extrinsic parameters?
cameraLocation = -camExtrinsics.Translation/camExtrinsics.R; or in other words if , the optical center is at .

2 days ago | 0

Answered
Vectorize a nested loop
EDITED: R=10; K=size(lambda_tol_vector.Value,1); CompletedMat_parvec=cell(R,K); B=double(B); parfor n=1:R*K ...

2 days ago | 1

| accepted

Answered
Image segmentation for each slice in a volume stack
clear areas for i = size(stack,3):-1:1 ... all_areas = regionprops(area_filt, 'Area'); areas{i} = [all_are...

3 days ago | 0

| accepted

Answered
Trying to find the odd and even number from 3:200 using equation mentioned below
n = 3:200; even=~rem(n,2); x = (n-3)/2 + 1 ; x(even)=(n-4)/2+0.5;

3 days ago | 0

| accepted

Answered
How to fit a function that has significant changes dependent on small changes of some parameters
Change the units of L to something smaller. Stop trying to measure the distance between houses in kilometers rather than in met...

3 days ago | 0

Answered
Differences in power law fit vs. linear fit on log-log scale
There is a difference because the statistical distribution of the measurement errors changes under the log transformation. You s...

3 days ago | 0

Answered
Detecting maximum with threshold
If you have the time, please look over my work and provide some guidence. In detectThreshold(), you need to add control logic ...

3 days ago | 0

Answered
I want to turn this code into led light instead of red ones
Is this what you want? IMG=load('Image').A; c=regionprops(all(IMG>250,3),'Centroid').Centroid; %LED centroid/position ims...

3 days ago | 0

Answered
Logical Indexing of Meshgrid
Logical arrays can be 3D just like any other Matlab array (except tables and 2D sparse matrices). You can use volshow to get a 3...

3 days ago | 0

Answered
I want to find distance of an object in various of images
See triangulate().

3 days ago | 0

| accepted

Answered
How do I find the distance from 2 cameras to an object?
See triangulate().

3 days ago | 0

Answered
iterating with predefined submatrix range
section_1 = {10:15, 6:18; 9:15, 6:20; 12:13, 34:36}'; for s = section_1 [i,j]=deal(s{:}); T(i,j, k + 1) = t_human *(T...

3 days ago | 0

Answered
How to vectorize the evaluation of a kernel function.
K=1./pdist2(x_points,y_points);

3 days ago | 2

Answered
Can we manipulate a file without opening it
If you have one single file, the reading and saving of the file should probably happen outside the loop. Use the parfor loop to ...

5 days ago | 0

Answered
Incompatible sizes of arrays.
but i got error "Arrays have incompatible sizes for this operation." Can someone explain why? It should be obvious from the d...

6 days ago | 0

Answered
Optimization: Capacitated Facility Location Problem
x=optimvar('x',[n,m],'Upper',0); y=optimvar('y',n,'type','integer','Lower',0,'Upper',1); objective=sum(f(:).*y(:))+sum(c(:)....

6 days ago | 2

Answered
How to plot an Ellipse
Using this FEX download, https://www.mathworks.com/matlabcentral/fileexchange/87584-object-oriented-tools-for-fitting-conics-an...

6 days ago | 0

Load more