get 2 set of random coordinates

How to plot as above randomly with two colors

I have now given

xy = [2.5 4.5;

3.5 4.5;

4.5 4.5;

4.5 2.5;

3.5 3.5];

and plotted

what should i do to get 2 set of random coordinates and plot as shown in image attached. All locations should have a plot

[Adam Danz]

Your title seems like you want to choose 2 colors randomly but the last sentence seems like you want to produce random coordinates. Can you explain the problems again?

[Elysi Cochin]

i want to select 2 set of random coordinates

Answer 1

[Adam Danz]

In this demo, I create a grid of coordinates identical to the plot in your question. Then I randomly select a subsection of them. Then I plot that subsection in red and the remaining coordinates in black.

%Produce coordinates
[x, y] = meshgrid( [1.5:1:5], [1.5:1:5]); 

% randomly select a subset of coordinates
idx = logical(randi([0 1], size(x))); 

% plot each subset
figure
plot(x(idx), y(idx), 'ro', 'markersize', 15, 'linewidth', 2); 
hold on
plot(x(~idx), y(~idx), 'ko', 'markersize', 15, 'linewidth', 2); 
xlim([1, 5])
ylim([1, 5])

% add grid
set(gca, 'xtick', 1:5)
set(gca, 'ytick', 1:5)
grid on

The figure produce is below (each reproduction will randomly select a different subset).