# 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.

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**Content Feed**

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',...

ongeveer 16 uur ago | 0

Area between three curves

A=Einspeiseanteil; B=GabelstaplerP; C=max(A,B); area=trapz(X,(C-Y).*(C>=Y))

ongeveer 21 uur 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...

1 dag ago | 0

How can I assign values to min/max of a column within each value of another column?

Let's call your table T, then, T=table(randi(2,10,1), randi(100,10,1), rand(10,1),'V',{'Device','Time','current'}) str=[""...

1 dag ago | 0

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min and max optimization as a single minimization function

if i am adding these function together like as follows min(f)=(1/f1)+f2 will it be correct? can i get the proper result? The s...

1 dag ago | 0

4D matrix multiplication

steer=reshape( permute(steer,[2,3,4,1]),101^2,[],136 ); R=permute(R,[2,3,1]); F=1./sum( pagemtimes(steer,R).*steer, 2); ...

2 dagen ago | 0

plotting two lines intersecting at a certain point

This is equivalent to a first order free-knot spline fit. This FEX submission might be useful, https://www.mathworks.com/matlab...

2 dagen ago | 0

how do you create an array of 3d arrays

I've been trying different ways of using the cat function You haven't told us in what form the 15 stacks exist now. If you have...

2 dagen ago | 0

How to grow a vector in a loop?

coef=nan((ldiv+1)^2*(sdiv+1)^2,1); %PRE-ALLOCATE mm=0; for ii = 1:ldiv+1 for jj = 1:sdiv+1 ... ...

2 dagen ago | 0

Frequency Domain Filtering by Convolution Theorem

They are warnings, not errors, but if you expect your FFT/IFFT to be real-valued due to symmetry, you can do h2 = ifft2(h1,'sym...

2 dagen ago | 1

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How to grow a vector in a loop?

You could just vectorize everything. x_m = [sb_panel.xm]; y_m = [sb_panel.ym]; z_m = [sb_panel.zm]; ...

2 dagen ago | 1

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Efficient computation of the sum of pairwise absolute differences

This GPU implementation may also be useful. I was able to process a 500x500 matrix in 20 seconds on the GTX 1080 Ti. A = magi...

2 dagen ago | 0

Efficient computation of the sum of pairwise absolute differences

I think parallelization might be the only way to accelerate things. Parfor seems to work well with the rewritten version of diff...

2 dagen ago | 1

Efficient computation of the sum of pairwise absolute differences

The question: is there any way to make this work efficiently, ideally with conv2 or xcorr2? If you were taking the sum of squa...

3 dagen ago | 0

Matrix-vector operations without loops

A=2*(HessW(:,:)*GradW(:));

3 dagen ago | 0

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Linear fitting with 2 variables

Assuming f is 3x1, x=rand(1,15); %Example data f=rand(3,1); y=3*x+2+7*f; [F,X]=ndgrid(f,x); p=num2cell( [X(:), X(:).^0...

3 dagen ago | 1

| accepted

I want to implement these equations in MATLAB but how?

fn=@(theta,k) exp((0:k-1).' * (2i*pi*d/lambda*sin(theta))); A=fn(theta,M); B=fn(theta,N); y=reshape( A*B.', [],1);

3 dagen ago | 0

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How to get the camera scale factor

To get that, you need to image an object of known length at some known reference depth from the camera. You would also need to k...

3 dagen ago | 0

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solution of transcedental equation

eps1 = 1.5471; eps2 = 1.5431; eps1m = -9.894 ; eps2m = 1.0458; epsm = eps1m + i*eps2m; lambda = 633; k0 = (2*pi)/lambda;...

3 dagen ago | 0

Calculate the Median of the results from 100 Simulations

impOOB=rand(100,5) median(impOOB,1)

3 dagen ago | 0

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how to plot inequality and their intersection ?

The region prescribed by your inequalities is unbounded, so it is not clear what it means to "plot" it. If you really meant x<=2...

3 dagen ago | 0

How to rotate a 2d plot about the z axis to create a 3d object

See the cylinder command. https://www.mathworks.com/help/matlab/ref/cylinder.html t = 0:pi/10:2*pi; r = 2 + cos(t); [X,Y,Z]...

3 dagen ago | 0

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Randomly selecting a number from different arrays

A = [11 11 11 12 12 12 13 13]; B = [21 21 21 22 22 22 23 23]; C = [31 31 31 32 32 32 33 33]; M=[A;B;C]; I=mod(cumsum(ran...

3 dagen ago | 0

fmincon and the Objective function returned NaN warning

The sqp algorithm can recover from NaNs and Infs if your objective and constraint functions are finite on an open domain of x (I...

4 dagen ago | 0

Could you please help me to fit 2 circles so as to detect left and right half of breast?

Seems to me that you don't need to fit a circle, but rather to find the minimum bounding circle. For that, you could try minboun...

4 dagen ago | 1

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The longest consecutive values in a vector and the position at which it starts and ends

Using "Tools for Processing Consecutive Repetitions in Vectors", https://www.mathworks.com/matlabcentral/fileexchange/78008-too...

4 dagen ago | 0

Randomising a vector with respect to the probability of the outcome

I=randi(5,1,12); J=1:12; result=reshape( sparse(I,J,1,5,12) ,[],1); full(result(:))

4 dagen ago | 0

Creating artificial pictures based on an original picture

Sounds like a job for a GAN, https://www.mathworks.com/help/deeplearning/ug/train-generative-adversarial-network.html

4 dagen ago | 0

Plot for the following program is not showing up, i am trying to plot value of M1 for given L

M1 needs to be a vector: for L=1:799 if ____ M1(L)=____ elseif ___ M1(L)=____ else M1(L)...

4 dagen ago | 0