Community Profile # Les Beckham

Last seen: Today Active since 2013

Many years developing flight control algorithms and software

Programming Languages:
C

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Reveresing the order of columns in an array
% Note: use semicolons instead of commas for row breaks so you get 4 columns q = [1 2 3 4; 5 6 7 8; 9 10 11 12; 13 14 15 16; 17...

2 Tage ago | 0

Recognise specific pattern in timetable
One approach without requiring the Signal Processing Toolbox: load('answers.mat') % an approximation of your data x = data(:,1...

9 Tage ago | 0

Extracting 2 Far right characters
One approach that generates a cell array: tt= {'United Kingdom TR';'United Kingdom SR';'United Kingdom WR';'Worldwide TC'}; c ...

13 Tage ago | 0

How to Rescale X Axis in Plot
Since you didn't show the code you used to generate the plot or include the data, I'll have to guess what the problem might be. ...

16 Tage ago | 0

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'Replace' shortcut in editor for R2022
Ctrl-H

24 Tage ago | 1

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calculate time from alarm (variabel x) to event (variable y)
Try this t = [0;10;20;30;40;50;60;70;80;90;100]; % in sec; variables are generated every 10 seconds alarm = [0;0;1;0;1;0;0;1;...

27 Tage ago | 0

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This should work for any number of columns and it automatically detects the number of header rows and the variable names. t = r...

27 Tage ago | 1

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How do I resolve these two lines separately?
Another approach B=rand(3,5) A=[0 0 0 1 0;1 1 1 0 0;1 0 1 1 0] idx = B > 0.6 A(idx) = ~A(idx)

28 Tage ago | 1

Count number of words per row in a string
In 2020b or later you can also use a pattern with a regex pattern to find (and count) words. It took some experimenting to get ...

28 Tage ago | 0

Can yous tell me this block in Simulink
That looks like the XY Graph block, perhaps. It normally isn't orange, however.

28 Tage ago | 0

Calculating u and v components from wind direction and speed
Actually, it is straightforward. v (North (y) component) and u (East (x) component) can be calculated from S (wind speed) and D...

30 Tage ago | 0

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How do I calculate the acceleration using only 3D distances?
load acc_dist.mat xyz = cell_of_double_pre_ballsCopy{1}; dxyz = diff(xyz); % difference between adjacent points in xyz coordin...

etwa ein Monat ago | 0

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Plot is not showing anything.
Replace your loop with h= 0.1; %step size for loop t = 0:h:1; for i = 1:numel(t) xt(i) = X0*exp((-S)*wn*...

etwa ein Monat ago | 0

How can I use a variable for formatting?
You can also use %*d, like this for k = 1:5 fprintf('%*d\n', k, 2*k); % the first argument (k) is the field width, 2*k is ...

etwa ein Monat ago | 1

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Is there a bug in imread() or imfinfo() with multiframe GIFs in R2021a/b?
Output of your test script theonlymap = 1.0000 0.0824 0.9137 0 0 0 0 0 0 0 0 ...

etwa ein Monat ago | 0

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How to Create/Modify for matrices or matrix
K=5; matA = 1:K matB = repmat(matA, 1, K)

etwa ein Monat ago | 1

3D Profile Extrude
x = [82, 80, 65, 38, 82]; y = [82, 54, 36, 94, 82]; x = repmat(x, 10, 1); y = repmat(y, 10, 1); z = (1:10)'; z = repmat(z, ...

etwa ein Monat ago | 0

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Damping and natural frequency
The damping ratio that you calculated is greater than one, meaning this system is overdamped (non-oscillatory). It has two real...

etwa ein Monat ago | 1

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Matlab graph is not drawn
You aren't incrementing k or creating t in your loop. There are also other things wrong with your calculation of x. For one th...

etwa ein Monat ago | 0

Try and Catch for multiple conditions
Maybe something like this: if isfield(src, 'DeviceName') Name = src.DeviceName; else Name = 'unknown'; % or, just do...

etwa ein Monat ago | 0

Matlab is not recognizing the graph(...) function.
The graph function was added in release 2015b. See doc page here (the info on when it was introduced is at the bottom): https:/...

etwa 2 Monate ago | 0

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Filling an array with color points
j = 34; g = 3; A = zeros(j,g); A(:,3) = 1; % put ones in the third column A(:,2) = ([0:j-1]/j).'; % fill in the second colum...

etwa 2 Monate ago | 0

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How to change the type when creating HDF5 attributes.
I don't have any hd5 files to test this with, but I suspect that if you change this h5writeatt('tt.h5','/tide','Transient', "TR...

etwa 2 Monate ago | 0

Interpolating NaN values within a matrix
I would recommend the fillmissing function.

etwa 2 Monate ago | 0

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I try to run a for loop to plot the function y(t) for 0.1<=t<=0.9 for 5 diffrent t. Can you help me with my code?
You were pretty close. I had to change the loop to loop over the elements of t and save y one row at a time using y(i,:) using ...

etwa 2 Monate ago | 0

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I hope to show that aliasing occurs for more than one sinusoid
Perhaps you are looking for something like this? t = 0:1/500:0.02; x = 3*cos(2*pi*300*t+pi/3) + 8*cos(2*pi*800*t-pi/5); plot(...

etwa 2 Monate ago | 0

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How to append a string to a filename when saving a file?
This should get you closer to what you want to do [~,f,ext] = fileparts(files(id).name); % extract file name without original e...

etwa 2 Monate ago | 1

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How to use MATLAB RGB triplets and hexadecimal color codes for a custom plots?
I don't think you can specify name/value pairs in the plot command with multiple x/y values. This isn't very elegant but it d...

etwa 2 Monate ago | 1

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Cutting a Circular Ring at particular points using angle-theta
You were pretty close. See if you can adapt this to get what you want. p = linspace(-1/2,1/2,100); [X,Y] = meshgrid(p,p); % b...

etwa 2 Monate ago | 0

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