# 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.

**Content Feed**

How to solve large linear complex equations

Since it is a linear and unconstrained system of equations, just use mldivide, \

6 hours 前 | 0

Help with parametrizing a function and creating points

syms x y P [1,2] syms r(t) P1=[x1, y1]; P2=[x2, y2]; r(t)=P1+t*(P2-P1)

6 hours 前 | 0

How can i extract data from given variables, for suppose i want to extract charge and discharge separately.

I will assume your data is in a table: type=["charge";"discharge";"discharge";"charge"]; data=(1:4)'; T=table(type,data) ...

6 hours 前 | 0

Wanna find specific index(raw) which meet multiple(~3) conditions

use ismembertol to allow for floating point noise, Index = find( ismembertol([39,13.9,17.2],A, 1e-6,DataScale=1,ByRows=1) )

6 hours 前 | 0

Does anybody know what the exact meaning of the following command?

It defines an anonymous function of x,y. Everything after @(x,y) is the expression that will be evaluated. E.g., D=@(x,y) x+y; ...

11 hours 前 | 0

How can I import this data with a for loop?

Data{i} = importdata(compose("PendulumTestData/TD%d/IK/HR_1.mot", x(i)));

13 hours 前 | 2

How to interpolate 2 dimensions of a 4D array ?

You can use imresizen, to be downloaded from https://www.mathworks.com/matlabcentral/fileexchange/64516-imresizen-resize-an-n-d...

14 hours 前 | 0

How to avoid NaN in the Mini-batch-loss from traning convolutional neural network?

I found that changing the solver (from "sgdm" to "adam") resolved the problem.

19 hours 前 | 0

How to represent gray scale images as affine subspaces?

So how Can I get the direction and origins so I can compute the grassman distance? Here is another variant that gives a Basis/...

20 hours 前 | 0

how to get reference in app designer

It is possible, and what you've shown should have worked, unless your Matlab version is really old. The Code view should show t...

1 day 前 | 1

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How to convert values of 0 to NaN

NaNs will not appear bright on an image display. You would have to replace them with a large value. Image(Image==0)=brightValue...

1 day 前 | 0

How to have a class that contains multiple functions that is used in other classes?

A static class method can be imported from a package like in this example, https://www.mathworks.com/help/matlab/ref/import.htm...

1 day 前 | 0

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Adding zeros to a column vector to match a larger column vector

This gracefully handles the case when length(x)=length(y), and requires no consideration of whether x,y are row or column vector...

1 day 前 | 0

Is Conv2 based on direct convolution?

It is not FFT-based. To do FFT-based convolution (using the overlap-and-add method) you could use fftfilt.

1 day 前 | 1

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How to draw a generic cylinder with arbitrary orientation

See this File Exchange download, https://www.mathworks.com/matlabcentral/fileexchange/87584-object-oriented-tools-for-fitting-c...

1 day 前 | 0

Loading files by replacing some part of the name with a variable

Pre-generate all of the filenames and loop over them. FileNames = compose("GNSS_Validierung_%.2d",(1:41)' )

2 days 前 | 0

Facing problem in solving simultaneous nonlinear equation with 3 unknowns

What @Dyuman Joshi says is true. However, your equations don't seem to make sense without upper and lower bounds on x. For examp...

2 days 前 | 0

Assigning row names iteratively

The row names of a table cannot be non-unique, so having the names of the 7 days of the week repeat 52 times would not generate ...

2 days 前 | 0

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Plotting a giant surface exceeding array limitations

First of all, you should consider downsampling from 40000 points to perhaps 400. Having very dense data beyond a certain point w...

3 days 前 | 1

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Partial Fourier transform of large sparse 3D array

There is at most 1 nonzero pixel in each x-y plane (first 2 dimensions) ... I'm thinking of doing 1D Fourier transform on each d...

3 days 前 | 0

Partial Fourier transform of large sparse 3D array

You can do the partial Fourier transforms by computing a set of partial DFT matrices: dftPartial=@(N,k)sparse(exp(-(2j*pi/N)*(0...

3 days 前 | 0

Adding more values to an array every loop

One possibility, y=nan(1,100); s=0; for k=1:numel(y) y(k)=2*k-1; s=s+y(k).^2; if s>40, y...

4 days 前 | 1

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My ellipse wont close after running the code .

Can't you just use the native spline() command? theta = linspace(0, 2 * pi, 8); t_x = 2*cos(theta); t_y = sin(theta); dt_x...

4 days 前 | 0

Newton Raphson to solve a system of non-linear equations

From the surface plot, the equations don't appear to have any solution, or at least no where near the vicinity you are searching...

4 days 前 | 0

Why is my gamultobj algorithm not working?

My guess would be that it is struggling to find feasible solutions to the nonlinear constraints (perhaps because they don't have...

5 days 前 | 0

Solve large number of independent systems with fsolve, where some systems do not have a solution

I see no reason why fsolve would "give up" if you've set MaxIterations and MaxFunctionEvaluations to Inf, regardless of whether ...

5 days 前 | 0

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Display long strings that include newlines in a table

I don't think there's a way. But you could write to an Excel file (e.g., with writetable) where multiline cells are possible. >...

5 days 前 | 0

Dot indexing is not supported for variables of this type.

Have you actually looked at the contents of device? Is it possible that MAI.GetDeviceByIndex(0) returns empty [] because someth...

5 days 前 | 0

understand in which function the field is filled

If ReportAggreg is created literally with an assignment statement of the form someStruct.ReportAggreg = something it should be...

5 days 前 | 0

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Can I define the relationship between input and output using the raw experimental data in MATLAB. somthing like this .

Yes, you have a choice of lsqcurvefit, fit, and various others.

5 days 前 | 0