# How to count the number of scatter points of each color

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muhammad farttoos on 8 Jun 2024
Answered: Steven Lord on 10 Jun 2024
I have make a code that do the scatter points in a graph, but i need to find the number of scatter points of each color? i have attached the sample code and graph for explaintion
for h=num_fixed_nodes+1:1:num_nodes
%Generate random nodes within the region
S1(h).xd = position_region(i,1) + rand(1,1)*region_width;
S1(h).yd = position_region(i,2) + rand(1,1)*region_height;
S1(h).G=0;
S1(h).id=h;
S1(h).type='N';
S1(h).temp = interp2(aa1,bb1,temp_values_1,S1(h).xd,S1(h).yd);
S1(h).E=Eo*rand(1,1);
Et=Et+S1(h).E;
S1(h).node_status = S1(h).temp<thresh_temp;
if(S1(h).node_status==1)
scatter(S1(h).xd,S1(h).yd, 'filled','MarkerFaceColor','g');
else
scatter(S1(h).xd,S1(h).yd, 'filled','MarkerFaceColor','r');
end
end

Voss on 8 Jun 2024
```idx = [S1(num_fixed_nodes+1:num_nodes).node_status]==1;
n_green = nnz(idx);
n_red = nnz(~idx);
```
muhammad farttoos on 10 Jun 2024
Voss on 10 Jun 2024
You're welcome! Any questions, let me know. Otherwise, please "Accept" this answer. Thanks!

Steven Lord on 10 Jun 2024
Rather than creating one scatter plot for each individual point, I'd use that loop to create a vector of data that indicates in which color each point should be plotted then call scatter once after the loop is complete, passing that vector in as the c input argument. In that case you could use the groupcounts function to count how many elements of each color are in c.

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