Hi, I am relatively new to Matlab, and I have a question regarding the function pdist(), I have a following code:
% RA Dec
A = [00 08.2 +29 04 12 54.0 +56 00 12 55.4 +3 25 17 58.8 -9 46 18 05.6 -30 25 23 03.7 +28 04 23 04.6 +15 11 23 39.3 +77 36]; Ar = [A(:,1)+A(:,2)/60 A(:,3)+A(:,4)/60]; [X,Y,Z] = sphere; [RAx,DCy,Zz] = sph2cart((Ar(:,1)*2*pi), Ar(:,2)*pi/180, ones(size(Ar,1))); figure(1) hm = mesh(X,Y,Z); hold on plot3(RAx, DCy, Zz, 'h', 'MarkerSize',5, 'MarkerFaceColor','b') hold off axis equal off set(hm, 'EdgeColor', 'k', 'FaceAlpha',0.5) view(55,20) distance = pdist(Ar,'euclidean'); Z = squareform(distance);
basically A is the right ascension and declination of a particular star, and I used the pdist(Ar,'euclidean') to obtain the distance between any 2 points.
The question is: Does the distance obtained by "pdist" equal to the distance between 2 points on a sphere or is it on a 2D plane?
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