Remove 2D array elements outside of a range

Hi,

I am attempting to remove array elements that fall outside of specified ranges. The array I am working with is 199x199 (wmax), and there are subsequent 199x199 arrays that contain both longitudes (x_pts) and latitudes (y_pts).

Essentially I want to create a smaller array that only includes data within 2 given latitudes and longitudes. Whenever I try this, it returns an N x 1 array, but I am hoping for a 2D array to be returned.

wmax(x_pts>-103&x_pts<-100&y_pts>34.75&y_pts<36.5;

Answer 1

[Voss]

Try one of these two things, depending on whether x_pts corresponds to the rows or columns of wmax:

% if x_pts corresponds to the rows of wmax and y_pts is the columns:
wmax(x_pts>-103 & x_pts<-100, y_pts>34.75 & y_pts<36.5);
% if x_pts corresponds to the columns of wmax and y_pts is the rows:
wmax(y_pts>34.75 & y_pts<36.5, x_pts>-103 & x_pts<-100);

Example:

x_pts = 1:10;
y_pts = 102:109;
% x_pts goes with rows, y_pts goes with columns, in this case
wmax = randn(numel(x_pts),numel(y_pts))

wmax = 10×8

0.1245 -1.1668 -0.0475 0.5001 -0.2800 1.3163 0.6479 1.2807 1.5173 0.6925 -1.1350 0.5612 2.2336 0.8672 0.3282 -0.2573 -0.6798 1.2087 1.1384 1.8517 1.2552 -0.5807 -0.5476 1.7234 1.1392 -0.7541 0.5278 -0.1743 -0.3634 -0.0129 -1.1077 -0.0505 -0.9966 0.0368 0.0110 -1.2554 0.4684 -2.0030 2.2644 -0.1099 0.0899 -0.0061 -1.2089 -0.4280 -0.8558 1.5466 -0.7792 0.3896 -0.6317 0.0086 0.9400 0.1565 -0.5707 0.1088 -0.5228 -1.4621 0.1477 0.7005 0.1280 0.1691 -0.8256 0.9573 0.7240 1.3552 0.5469 -0.5682 0.0907 1.2396 -1.5674 -0.7999 -1.1673 0.6018 0.7427 -0.5076 1.3764 -1.8479 -0.4785 0.0112 -1.8359 0.3773

wmax(x_pts>3 & x_pts<7, y_pts>105 & y_pts<108)

ans = 3×2

-0.3634 -0.0129 0.4684 -2.0030 -0.8558 1.5466

[KCE]

I have tried this along with multiple combinations, and they all seem to return a 1D answer.

[Voss]

Make sure you have the comma where you had an & before:

wmax(x_pts>-103 & x_pts<-100, y_pts>34.75 & y_pts<36.5);
%                           ^

If that's not the problem, then can you demonstrate it here, with an example? Either construct a small matrix along with two vectors to use for indexing into the matrix, or save your variables to a mat file and upload it (with the paperclip button).