how to use "for loop" for firstly entering into each rectangular grids then find minimum distance b/w nodes in each grid

here i want to apply for loop for each 16 rectangular grids then after entering into the grid i want to find eucledian distance b/w the nodes present in that grid

[KSSV]

You have to clarify many things: There is a grid with 16 elements (boxes). Inside each box there are points..you want to find the distance between what and what?

[kiranpreet kaur]

sir, i want to find distance b/w each random nodes present with in each boxes

[kiranpreet kaur]

sir,i knows how to find distance b/w each nodes but i don't know the syntax to enter inside each box and then find distance b/w the nodes present randomly in each box. for example i want to goto in first box then i have to apply minimum distance operation on the nodes present in first box.............for this procedure how could i use for loops plz sir tell me the nested for loop syntax for this procedue. sir plz help me with a syntax for my problem

Answer 1

[KSSV]

close all;
clc;
ngrid=4;%no. of grids
N=200;
R=0.5;
sink.x=3.1;
sink.y=3.1;
x = linspace(0, 4, ngrid+1);
E=0.5;
[X,Y] = meshgrid(x);
figure(1)
plot(X,Y,'k')
hold on
plot(Y,X,'k')
hold on
ngrid = 4;
coords = rand(N,2) * ngrid;
nodes = struct('x',coords(:,1),...   %# Assign x coordinates
               'y',coords(:,2),...   %# Assign y coordinates
               'energy',E);

scatter(coords(:,1),coords(:,2));
set(gca, 'XTick', 1:ngrid+1, 'YTick', 1:ngrid+1)
axis square
plot(nodes.x,nodes.y,'o','LineWidth',2,   'MarkerEdgeColor','m','MarkerFaceColor','m','MarkerSize',3)
plot(sink.x,sink.y,'d','LineWidth',2,   'MarkerEdgeColor','r','MarkerFaceColor','y','MarkerSize',12)
grid on;
%%Get nodes inside for each box 
P1 = cell(4,4) ;
for i = 1:4
    for j = 1:4
        A = [X(i,j) Y(i,j)] ;
        B = [X(i+1,j+1) Y(i+1,j+1)] ;
        idx = find(nodes.x >= A(1) & nodes.x <B(1)) ;
        idy = find(nodes.y >= A(2) & nodes.y <B(2)) ;
        id = intersect(idx,idy) ;
        P1{i,j} = [nodes.x(id) nodes.y(id)] ;
        % plot points inside first box 
        plot(P1{i,j}(:,1),P1{i,j}(:,2),'*g')
    end
end

I have added a code to separate the points in each box.....P1 is a cell..it has all the points associated w.r.t box.

P{1,1} gives points inside first box.....P(3,2} gives points inside 3 row 2 column box....

Good luck

[kiranpreet kaur]

thanks for ur help sir,................ sir i want to find eucledian distance in P(3,2)...bcoz according to me when i find the minimum distance b/w the nodes it shows the minimum distance of nodes of whole network .............I just only wants to find the minimum distance in P(3,2).plz help me sir.....i would be very thankfull to u.........help me with a syntax