Sort and extract elemets from a structure.
tables are a vastly superior way of handling this data. Does this do it? mydata= readtable('mytext.txt'); sorted_data = sortro...

2 months ago | 0

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How to extract values from each structure in the .mat file
keeps the names, but as fieldnames in a new struct, signals, rather than variables (see Walter's comment): data = load('data.ma...

2 months ago | 1

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Changing the size of an array in a while loop
keeps the vector the same length A_i = gradient(A_0,dt).*I.^2; changes size of vector (and uses a for loop since there are a...

2 months ago | 0

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I have the following Matlab code that produces a x2 zoomed image of the input using Pixel Replication. How can I change it to shrink an image?
throw out every other row and column: img1 = imread(filename); N = img1(2:2:end,2:2:end);

2 months ago | 0

Copy files from a folder to another directory
check out dir and copyfile. My suggestion would be to create the lists of file and folders first, check them, then do something ...

2 months ago | 0

How can i create a vector having 6 values between two numbers
Assuming you want them evenly spaced: x = linspace(2,12,6); If you want them randomly spaced x = [2 ; 2+(12-2)*rand(4,1) ; ...

2 months ago | 0

How to combine indexing?
There may be a better way, but this should work: % set up a logical-indexing vector that selects no elements idx_Ev_not_Art = ...

2 months ago | 0

MATLAB Answers Wish-list #5 (and bug reports)
Being able to collapse items in the activity feed would be useful. Fairly regularly, I have 3-7 items for "X commented and edite...

2 months ago | 4

Compacting a For Loop
norm_er = 1.301; exp_er = 9.126; log_er = 1.301; ray_er = 2.606; Errors = [norm_er,exp_er,log_er,ray_er]; % set a tolerance...

2 months ago | 0

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Wondering about the efficiency of my code or if there is a better way to do what I am trying to do?
generally, deleting columns (esp. one-by-one) is less efficient than indexing. Assuming all of the tests have passed, you can si...

2 months ago | 0

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Looking for the RGB values of the 8-bit 256 colours?
finish reading the posted info: "An 8-bit display can produce any of the [2^24] colors available on a 24-bit display, but only 2...

2 months ago | 0

Which function should I use for generating the weighted least squares fit linear line for a given data?
fitlm accepts weights as a vector, but doesn't come with any pre-designed ones mdl = fitlm(x,y,'Weights',weight); Ypred = pred...

2 months ago | 0

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fprintf table not aligned
generally, I suggest not using tabs when you want a table aligned. Instead, set the field widths larger: fprintf('%6.2f %9.3f %...

2 months ago | 0

How do separate plot into months?
probably easiest would be to create a datetime object: % sample data data = rand(1,8760); % starting year/month/day of data ...

2 months ago | 0

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Fit a curve to a nonlinear 1D data
x=1:12; y=[18.92, 21.6, 27.4, 43.07, 85.66, 230.12, 347.02, 289.74, 197.32, 95.32, 39.5, 19]; % fit to a quadratic (degree 2) ...

2 months ago | 0

"Plot" image with size, position and rotation
see this question: Plot a figure in which there is an image that moves and rotates

2 months ago | 0

Loop to separate rows in one matrix and delete elements in that matrix based on another matrix
% find indices where z_probs<0.5 idx = (z_probs(:,:,1)<0.5); % "remove" those values in b_loc by setting them to NaN b_loc(id...

2 months ago | 0

need help for transfer Whlile loop from For loop
First issue: for loop ends when error<tol while loop continues when error<tol

2 months ago | 0

Plotting part of an array
simplest: xlim([0 0.2])

2 months ago | 0

Rotate Spherical Coordinates to find new Vector Magnitude
It sounds like the goal is to find the projection of the vector along the direction defined by theta=100, phi=150. If this is th...

2 months ago | 0

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Move colorbar location to the east in tiled layout figure
does this work: cb = colorbar; cb.Layout.Tile = 'east'; (from the colorbar documentation)

2 months ago | 0

Find indicies of k smallest matrix elements
[~,idx] = mink(A,2);

2 months ago | 0

Finding 4 closest values to a value in an array
use mink [~,idx] = mink(abs(data-find_point),5); data(idx)

2 months ago | 0

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How to get Y-values from X-values?
if you just want the Y value for the nearest point: [~,idx] = min(abs(X-certainX)); certainY = Y(idx); I don't see quite th...

2 months ago | 0

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How to increase fontsize of matlab IDE?
there is a workaround here that probably still works: https://www.mathworks.com/matlabcentral/answers/233543-how-to-change-the-...

2 months ago | 0

Can you plot polarplots so that theta zero location is at any arbitrary angle or are top left bottom right the only options?
something like this: top_angle = 24; % get current labels tt = thetaticks; % rotate angles so top_angle takes place of 90 t...

2 months ago | 0

How to plot many curves on a x-y-x axis system
sounds like plot3 is what you want, though I'll warn you that getting readable figures out is more an art than a science

2 months ago | 0

How do I display the first 20 numbers of the Fibonacci sequence?
you need to define the first two numbers manually, then start on the third f(1) = 0; f(2) = 1; for a=3:20 ... Also, it's un...

2 months ago | 0