compare 2 matrix with different dimensions

Hi, assume that I have a matrix 'info' (800,3), the first column is for ID, the second column is for coordinate x and the last column is for coordinate y. Additionally I have a matrix called 'coordinates'(200,2) where the first column is coordinate x and the second is coordinate y. I want to compare this matrix with the 'info' matrix to find the IDs where the matrix 'coordinates' is equal to the 'info' matrix.

Thanks

[Walter Roberson]

Are the coordinates integers?

http://matlab.wikia.com/wiki/FAQ#Why_is_0.3_-_0.2_-_0.1_.28or_similar.29_not_equal_to_zero.3F

Answer 1

[Walter Roberson]

[tf, idx] = ismember( info(:,2:3), coordinates, 'rows');
match_IDs = info(tf, 1);

Answer 2

[Azzi Abdelmalek]

A=[1 10 20;2 100 200;3 1000 2000;4 44 55]
B=[11 20;100 200;1 4;44 55 ]
out=A(~any(A(:,2:3)-B,2),1)

[Vanessa]

Hi, when I use this I get an error

??? Error using ==> minus Matrix dimensions must agree.

I hope you can help me

[Angus]

I am wondering does this only output IDs that had matching 'x' values? I am asking as I am interested in how the 'any' function works. Does it only work down one vector?

[Azzi Abdelmalek]

Ok, it does not work, look at Walter's answer

[Vanessa]

sorry, my matrix was wrong, I fixed it and it works, thanks

[Walter Roberson]

any() by default works along the first dimension (so down columns), but it accepts an optional dimension number. dimension #2 means across rows.