f I have a circle and i generated 50 random points inside , how can i assign unique id to every random point inside it , i want to have like user(1),us​er(2),....​.,user(50) ? so i can call any point inside the circle with this id

f I have a circle in matlab and i generated 50 random points inside , how can i assign unique id to every random point inside it , i want to have like user(1),user(2),.....,user(50) ? so i can call any point inside the circle with this id i have these two codes to make a circle and generate the random points inside it if I have a circle and i generated 50 random points inside , how can i assign unique id to every random point inside it , i want to have like user(1),user(2),.....,user(50) ? so i can call any point inside the circle with this id i have these two codes to make a circle and generate the random points iside it

%%// Plot the circle 
x = linspace(-sqrt(10),sqrt(10));
 y1 = sqrt(10-x.^2); 
y2 = -sqrt(10-x.^2); 
plot(x,y1,x,y2)
 axis equal

%%// Choose from 1000 random point pairs 
c=[0 0];
 N = 1000;
 %%// Radius of circle
 radius = sqrt(10);

%%// Create a random point matrix Nx2 
points_mat = [ radius*2*(rand(N,1)-0.5) radius*2*(rand(N,1)-0.5)];

%%// Select the first 50 pairs that lies inside circle 
ind1 = find(sqrt( points_mat(:,1).^2 + points_mat(:,2).^2 )<radius); points_mat=points_mat(ind1(1:50),:);

%%// Plot the 50 points on the circle
 hold on
 text(0,0,' Center') %%// Center

text(points_mat(:,1),points_mat(:,2),'n') %%// 50 points

%// Set parameters
 R = 15; %// radius 
C = [0 0]; %// center [x y]
 N = 50; %// number of points inside circle

%// generate circle boundary 
t = linspace(0, 2*pi, 100);
 x = R*cos(t) + C(1);
 y = R*sin(t) + C(2);

%// generate random points inside it 
 th = 2*pi*rand(N,1);
 r = R*rand(N,1);

xR = r.*cos(th) + C(1); 
yR = r.*sin(th) + C(2); zR=[xR yR];

   %// Plot everything 
  figure(1), clf, hold on
   plot(x,y,'b') plot(C(1),C(2),'r.', 'MarkerSize', 60)
   plot(xR,yR,'p') 
  axis equal

Answer 1

[Image Analyst]

I don't understand. xR HAS a unique label for every point - it's the index! You don't need anything more. However if you want it as a separate row, then do

newX = [1:length(xR); xR];

[Meme]

thank you

Answer 2

[Walter Roberson]

Store the coordinates in a 2D matrix and use the row number, so user(5,:) for example.

Or use a cell array and use {} instead of (), so user{5} for example.

[Meme]

thank you