Matt J

Last seen: Today

7,446 total contributions 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.

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Answered
How to fit an exponential curve? error: Dimensions of arrays being concatenated are not consistent
Did you mean, [[ones(size(time)); -exp(-time)].\E_f; ones(size(time))]

2 days ago | 0

Answered
Why does subclassing a numeric type break its use as a property of a custom class?
1. Why does my code work for double but not ExtendDouble? The ExtendDouble example is old. It's subsasgn() method was not writt...

3 days ago | 2

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Answered
How can I create a vector like this : X = [1, 2, 1, 2 ......
X=ones(1,n); X(2:2:end)=2;

3 days ago | 2

Answered
For loop with nested if loop
Perhaps this is what you want, condition=( (HipVel > .0014) & (KneeAngle < minAngle); drop_time = VJ_P1_T1.data( condition ...

3 days ago | 0

Submitted

whosGPU
Provides WHOS-like output for gpuArray variables in the current workspace.

3 days ago | 1 download |

Answered
General conic curve fit with constrained coefficients
Here's a basic analytical fit, using the tools in this File Exchange package: [xy,T]=conicFit.homogNorm([x(:),y(:)].'); x=xy...

4 days ago | 0

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Answered
How to check the Bytes of gpuArray?
See whosGPU (Download).

4 days ago | 0

Answered
Obtain memory usage and class for GPU variable
See whosGPU.

4 days ago | 0

Answered
GPU equivalent of "whos" or "feature memstat" ?
See this File Exchange submission, https://www.mathworks.com/matlabcentral/fileexchange/88024-whosgpu

4 days ago | 0

Answered
Fontsize using Latex interpreter
You can set fontsizes as shown here, https://www.mathworks.com/matlabcentral/answers/350036-latex-interpreter-with-sentences-an...

4 days ago | 0

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Answered
how to write a bisection loop?
Because y is a polynomial, it is much more expedient to use roots(), y = [(-0.50598*10^-10) , (0.38292*10^-7) , (0.74363*10^-4)...

4 days ago | 0

Answered
How to compare two strings with different sizes?
Another guess: a = 'AAGCTACGC'; b = 'ACGCAA'; match = ( a(:)==b )

4 days ago | 0

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Answered
feval distorted in ga after using nonlinearconstr
The main thing I see that looks out of place is that is the role of SSP_restored_1st15day. If it is a variable, I cannot see wh...

6 days ago | 0

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Answered
How can I plot ln(1-x)/x using colon operator?
x = linspace(-10^(-15),10^(-15),300); f = log(1-x)./x; plot(x,f)

6 days ago | 0

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Answered
How to plot a graph that I already have in on paper
Yuo can use this, https://www.mathworks.com/matlabcentral/fileexchange/7173-grabit to extract the points on the curve, which y...

6 days ago | 0

Answered
Check if nullspace is contained in another + finding intersection of 2 nullspaces.
Hints: (1) Consider [null(A), null(B)] (2) Consider [A;B]

6 days ago | 1

Answered
Linear programming code not showing the solution
As long as your feasible set is bounded, you can use this FEX submission instead, https://www.mathworks.com/matlabcentral/filee...

6 days ago | 0

Answered
exp(-b/x) fit, inf problem when fitting
When x goes to zero, y should go to zero as well since anything power negative infinity is zero. Only if b>=0. g = fittype('ex...

8 days ago | 0

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Answered
accumulating unique indices in array
B = histcounts(A,1:max(A)+1)

8 days ago | 0

Answered
Sum subarrays of a Matrix.
Using sepblockfun https://www.mathworks.com/matlabcentral/fileexchange/48089-separable-block-wise-operations out=sepblockfun(A...

8 days ago | 1

Question

Recover former state of Matlab Editor
I had quite a few files open in the Matlab Editor, but then inadvertently closed the editor window. Is there any way to re-open ...

9 days ago | 1 answer | 0

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answer

Answered
How to calculate reveral summations
T=triu(ones(600)); I=(1:600).' + (1:600); ur=u(:).'; sigma= (T.*ur(I))*ur(1:600).';

9 days ago | 0

Answered
How to calculate reveral summations
Use conv() or xcorr().

9 days ago | 0

Answered
How do I minimize a particular error function with lsqnonlin?
I don't see much that I think can be improved, except perhaps to formulate it so that your errors are differentiable - the lsqno...

9 days ago | 0

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Answered
Get "@" back in a table header (R2017b) when saving
For example, T=table(1,'VariableNames',"name_domain") T.Properties.VariableNames = replace(T.Properties.VariableNames,'_','@...

9 days ago | 0

Answered
How to find splitapply for multiple values
[G, idOcc,idAge] =findgroups(x.occupation,x.Age)

10 days ago | 0

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Answered
Calculation the mean of a portion of a matrix
mean( z(2:end-1,2:end-1) ,'all')

10 days ago | 0

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Answered
Rank one decomposition of a positive semi-definite matrix with inequality trace constraints
Is there any ways I could do the rank one decomposition of matrix X, such that The obvious answer seems to be to test each k to...

10 days ago | 0

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Answered
create matrix of integers with specified sum in column and row
You can try to formulate it as an integer program. M=optimvar('M',[4,4],'type','integer'); Constraints.columns=sum(M,1)<=col...

10 days ago | 0

Answered
Finding Upper and Lower Indexes
A = [1;2;3;4;5;8]; B = [3.5;6;2]; c=interp1(A,A,B,'previous'); C=[c(:),c(:)+1]

13 days ago | 1