How do I get the x,y coordinates from the scatter graph I generated?

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ker fang fang on 2 Nov 2014
Answered: Image Analyst on 2 Nov 2014
Hi, I need to get those values to put into an equation. Can anyone help me? Here is the example code that I wrote. Thanks.
xrange = 0:100;
yrange = 0:100;
a= randi(numel(xrange),15,1); %randomly choose xcoordinate
b = randi(numel(yrange),15,1); %randomly choose ycoordinate
scatter(a(:),b(:),2000,'r')
for k=1:numel(a,b)
text(a(k),b(k),['(' num2str(a(k)) ',' num2str(b(k)) ')'])
end

Zoltán Csáti on 2 Nov 2014
You created the scatter plot in view of vectors a and b. So those are the coordinates. Supposing you only have the scatter plot and you want to extract the coordinates:
sc = findobj(gca,'Type','hggroup');
xCoord = get(sc, 'XData');
yCoord = get(sc, 'YData');
Zoltán Csáti on 2 Nov 2014
I do not really know what you want. You have vectors a and b at disposal.

Image Analyst on 2 Nov 2014
The answer to your question is that you already have "a" and "b" so you have the "x,y coordinates" that you're requesting. Like Zoltan already told you, there is no need to call get() to extract it from the plot when it was YOU who created the plot - you must have the coordinates to create the plot in the first place.
If you want some kind of interpolated surface for every value of a and b, even those where you don't have any training data, try scatteredInterpolant().