# i have Grid points and its coordinate x, y, z. I want to find out Grid point given x, y and z.

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Pappu Murthy on 6 Oct 2016
Commented: Pappu Murthy on 7 Oct 2016
I have a set of Grid Points 1 thru N, and each has coordinated x, y and z.
Now I like to know how to get the Grid point number given x, y and z.

KSSV on 7 Oct 2016
Let A be your coordinates of size Nx2 and P be the point to seek the nodal number.
n = find(ismember(A,P,'rows'),1);
Pappu Murthy on 7 Oct 2016
Thanks for this reply. I have one question. I did this problem the following way function[Vn] = VertexId(Gp,V) tempx = Gp(:,2:4)-repmat(V,length(Gp),1); tempx = sum(abs(tempx),2); tempx = tempx==0; [Vn]=find(tempx); In my array Gp (N,4)... the first column is Node number followed by x, y, z coordinates. V is x,y,z coordinates of querry node. I did 1000 times both ways and found that this way is 22 times faster than "ismember" approach this made me really curious and would like your comment on why so. Thanks again for very prompt reply and correct answer.