# Les Beckham

Many years developing flight control algorithms and software

**Programming Languages:**

C++, C, C#, MATLAB, Assembly

**Professional Interests:**

**Statistics**

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**Content Feed**

Generate a sinus signal and plot the output

Your tmax is huge so you are plotting many many thousands of cycles. Also, stem clutters up the plot with circles on every data...

15 hours ago | 0

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How do you change the transparency of multiple lines using "plot" if the lines are all different colors?

h = plot(rand(5)); % example plot. When you make your plot be sure to capture the handle % now set the alpha on all the lines ...

1 day ago | 0

Rounding towards zero or from zero

There is no tie involved in rounding 3.6. If you wish, you can use floor instead: floor(3.6) If x was 3.5 instead, that would...

4 days ago | 0

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Is it possible to have a file that changes it name depending on another variable?

Try this: % Button pushed function: SaveButton function SaveButtonPushed(app, event) PatientID = app.PatientI...

16 days ago | 1

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Condense code in Split string operation

If you put the filename in a string instead of a char vector you can do it in one line s = "xxx_yyy_zzz.xlsx" extractBetween(s...

17 days ago | 1

increasing amplitude of sine wave

Fs = 44100; dt = 1/Fs; StopTime = 3; t = (0:dt:StopTime-dt)'; Fc = 3000; A = linspace(0, 1, numel(t))'; y = A.*sin(2*pi*Fc...

29 days ago | 0

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How to search for previous values in a table?

This should do what you want. Note that the cell array in this case only has one cell because there are only two timestamp rows...

29 days ago | 0

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Match two variables list

Perhaps what you want is this: c = ["80ms,110ms", "110ms,140ms", "140ms,195ms", "195ms,250ms", "250ms,400ms", "400ms,550ms", "5...

1 month ago | 0

Formatting a vector to not include the first value

It seems like you could benefit from taking this introduction to using Matlab: Matlab onramp This is an example of very basic ...

2 months ago | 0

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Using plot handle to replot a graph

Read the documentation for the copyobj function. Here is an example: x = 0:0.1:10; y = [sin(x);cos(x);tan(x)]; for i = 1:3; ...

2 months ago | 1

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how do I swap both axes in the current plot

syms y U = y^2/2 - (3*y)/4; yrange = [0,1]; fp = fplot(U,yrange); plot(fp.YData,fp.XData) grid on

2 months ago | 1

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Code to determine a log of the mean for a column of numbers?

A = magic(4) logmean_col1 = log(mean(A(:,1))) max_col2 = max(A(:,2)) mean_col3 = mean(A(:,3)) mean_col4 = mean(A(:,4))

2 months ago | 1

Find unique number sets

A = [1 4; 2 3; 3 2; 1 4]; B = unique(sort(A, 2), 'rows')

2 months ago | 0

Why is Q=30 after the loop is ran?

B=1; Q=0; if B==1 && Q~=B Q=20; if B<0 || Q==20 % you just set Q equal to 20 on the line above so this condition is ...

2 months ago | 0

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How to plot the bode plot extracted from LTspice in Matlab?

I used the import tool to import the data as fixed width data (right click on the file in the Current Folder and select Import D...

2 months ago | 0

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If there is a coding "sqrt(sum(data(:,1:end).^2,2))" , so what is the function number 2 after comma?

That tells the sum() function to sum along the rows. See the documentation for sum here

2 months ago | 1

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Extracting data from a matlab figure and saving it as a .mat file

open('6000_1.fig') hl = findobj(gca, 'Type', 'line'); % find the lines x = get(hl, 'Xdata'); % extract the data y = get(hl, '...

2 months ago | 1

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Filling gaps in a vector using a secondary data set

rain1 = [nan nan 1:10 nan nan] % example data rain2 = [20:34] idx = isnan(rain1); % find where rain1 has nans rain1(idx) = ra...

2 months ago | 0

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Guessing the values of a function by using initial values

You don't have to "guess" the values of the function, you can just calculate them. Example x = [-20:.1:20]; y = x; [X,Y] = m...

2 months ago | 0

Replacing Values in Matrix that are not equal to 1 while excluding 'NaN'

test1 = [ NaN 2 9 2 -.23 NaN 3 2 -1 -1 NaN 6 -.4 -1 -.57 NaN] test2 ...

2 months ago | 0

Concatenating Edit Field value with an existing string in App Designer

First, if you are getting an error, that is usually what will help you (and us) figure out what is wrong so, please, post the co...

2 months ago | 0

How to tick the parameter in the plot of a parametric function?

Try this (or something similar): % Your original code t = linspace(0, 1, 1000); x = t.^2; y = t.^3; figure plot(x, y, '-'...

2 months ago | 1

Two easy questions (But I am confused)

Using smaller examples so we can see the results: S = magic(10) % sample matrix d = diag(S) % extract the diagonal elements %...

2 months ago | 0

How to plot a 3-D "hotspot" figure

I would suggest looking at this example for the scatter3 function: scatter3 with varying marker colors You could use your f(x, ...

2 months ago | 1

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How do I demagnify a help page?

Ctrl-Scroll Down will reduce the magnification

2 months ago | 0

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How can I programmatically open the results of a command in a new window without setting it to a variable?

I can only think of a way to do this in two steps rather than one. result = 2 + 2; openvar('result'); This should work in des...

2 months ago | 1

Efficient Way to find index of max column for each row

Are you wanting to find the column number of the maximum value in each row? If so, this is how you can do that: A = magic(5) %...

3 months ago | 0

Too many output arguments (five on output)

You are defining this function as a function that takes 5 input arguments and returns one output argument. function y_cubic=cub...

3 months ago | 0

Strange result in subtraction operation

The "obvious" result is 1.2e-14 not 1.12e-14 (the different last two digits in your original numbers at the 14 decimal place giv...

3 months ago | 0

Removing quotation marks in a string using for loop

The quotation marks are not actually part of the string. It is just displayed that way. Plus, since you are using strings inst...

3 months ago | 0

| accepted