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Jan


12,499 total contributions since 2009

It is easier to solve a problem than to guess, what the problem is.

Questions about FileExchange submissions are welcome - get my address from the code. I do not answer mails concerning questions in the forum.

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Answered
lock first app if second is running
You can use waitfor in the main function and provide the handle of the uifigure. [EDITED] I assume, that https://www.mathwork...

3 days ago | 0

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Answered
How to introduce a phase shift to a existing vector
This is not possible, if you do not have additional information. You can apply a phase shift with a certain number of elements, ...

14 days ago | 1

Answered
question regarding 'copyfile' function from folder to folder
This is exactly, what you find in the documentation. Please read: help copyfile doc copyfile [SUCCESS,MESSAGE,MESSAGEID] = ...

14 days ago | 0

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Answered
To take pictures from FLIR (Cx series) camera every 30 secs
Use a timer object and insert the code for taking a picture in its callback. doc timer

19 days ago | 1

Answered
Changing the name of a variable throughout the code but only want it to change in a section.
Copy the text block, which you want to modify, to a new editor window. Perform the wanted modifications. Copy the block back to ...

19 days ago | 0

Answered
How can I use "system" command with input without typing myself all the input everytimes ?
Please take a look into the documentation of dammif: https://www.embl-hamburg.de/biosaxs/manuals/dammif.html Here you can see h...

19 days ago | 1

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Answered
Efficient algorithm for a duplication matrix
For n=300 this needs 1.3 sec instead of 27.5 sec: tic m = n * (n + 1) / 2; nsq = n^2; D = spalloc(nsq, m, nsq); row = 1...

20 days ago | 1

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Answered
How to detect change in mean value of a signal
It is impossible to detect a change, if it occurs in the first or last few frames. Ist there only 1 change of the mean? Then f...

21 days ago | 0

Answered
How can I export only specific data from a text file to a matrix?
With some guessing, that you want the part behind ':Solar_Radio_Flux:' : Key = ':Solar_Radio_Flux:'; Str = fileread(FileName)...

23 days ago | 0

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Answered
Parse error help please
I guess, this line is failing: Jsx*der(wx) = (Fflz + Frlz)*w/2 - (Ffrz + Frrz)*w/2 + (Ffyv + Fry)*h; Yes, of course. In Matlab...

24 days ago | 0

Answered
Alternative to delaunayn function supported by MATLAB coder for the C++ code generation
Matlab uses qhull for the calculation of delaunayn. qhull is a library written in C, see here: http://www.qhull.org/ So it shou...

24 days ago | 1

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Answered
decrease the elapse time
The output of the profile is useful - thanks. The most time is spent here: [days(:,:,i), time(:,:,:,i), I(:,:,:,i), Ta(:,:,:,i...

24 days ago | 0

Answered
How would I change the color of the angular axes without changing the color of the grid lines in polar plot
AxesH = polaraxes; theta = 0:0.01:2*pi; rho = sin(2*theta).*cos(2*theta); polarplot(AxesH, theta, rho) AxesH.GridColor...

25 days ago | 0

Answered
I do not understand why my code still gives me errors
Index exceeds the number of array elements (1). Error in RK (line 8) k(:,1)=feval(fun,t(j),y(:,j)); After the line: ...

25 days ago | 1

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Answered
Index exceeds matrix dimensions ERROR
Using global variables is a bad programming style. It impedes the debugging massively. It is hard to find out, which code has se...

25 days ago | 0

Answered
How to convert 24-bit signed hex from .csv file to an array of decimal data?
dataTable = readtable('demo.csv'); data = table2array(dataTable(:,1)); data = strrep(data, '0x', ''); dataDec = b...

26 days ago | 1

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Answered
Indexing cell array similar to excell
Maybe like this: Data = rand(7, 25); % Example data, actually 177x25 Names = {'A 123', 'A 123', 'B 456', 'A 123', 'B 456', '...

26 days ago | 0

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Answered
Calling Matlab GUI popupmenu callback on click
No, there is no callback in the Matlab level. You can use the Java callbacks, if your "Matlab GUI" is a figure, see https://und...

26 days ago | 0

Answered
part of file name
s = ' Hello_World_2020 ' c = strsplit(s, '_') c{2}

1 month ago | 0

Answered
looping though multiple sub-directories
FileList = dir('C:\Base\Folder\**\*.nii'); for k = 1:numel(FileList) File = fullfile(FileList(k).folder, FileList(k).name)...

1 month ago | 0

Answered
How to open my .m files in App Designer?
You do not have to open the files to use a slider for te modification of a constant. You need to write the code as a function, w...

1 month ago | 0

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Answered
array values are overwritten
Prefer file names including leading zeros: image0001.jpg, image 0002.jpg etc. Then the numeical order equals the alphabetical or...

1 month ago | 1

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Answered
Delete table from GUI app variable
Perhaps you mean: delete(app.table)

1 month ago | 0

Answered
How to rename all instances of persistent variables?
Simply remove the persistent command temporarily, rename the variable and insert persistent again. You can open the file e.g. ...

1 month ago | 1

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Answered
How to update variable names after a "clear"
Clearing variables is rarely useful in Matlab, but a waste of time only. So on one hand it is not exactly clear, what you are as...

1 month ago | 0

Answered
Variable is not fully defined on some execution paths.
Does this help? tcell2 = cell(10,10); for t = 1:10 for s = 1:10 tcell2{t,s} = imcrop(pic2, ... [(t-...

1 month ago | 0

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Answered
How to select numbers?
F = rand(1,400); M = rand(1,400); Tf = log(-F) / 0.73; Tm = log(-M) / 1.2; It is hard to guess, what this means: "I should...

1 month ago | 1

Answered
I can´t save
Some virus scanners limit the write access to the user's Documents folder to block encryption trojans. Check the logs of the vir...

1 month ago | 0

Answered
Replace pixels in a matrix without using histeq
for i = 1:1:r %go through rows for j = 1:1:c %columns img_heq(i, j) = T(img(i,j) + 1); end end

1 month ago | 2

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