# How can I plot multiple rectangles (or circles) using the rectangle function without using a for loop?

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Ekim Ekiz on 31 Mar 2020
Answered: Athul Prakash on 3 Apr 2020
I need to plot multiple circles using the built in rectangle function. I have matrices that contain the x and y coordinates of the points that I want the center of my circle to be on. d is the diameter of the circles. The code I am using is below. I want to plot the circles without using the for loop in order to save time.
for i = 1 : size(x,1)
pos = [x(i)-d/2, y(i)-d/2, d, d];
rectangle('Position',pos,'Curvature',[1 1],'FaceColor','c','EdgeColor','k','LineWidth',1);
end

Athul Prakash on 3 Apr 2020
I don't think there is a way to 'vectorize' this code, you can't eliminate this for loop and achieve much of a speed up. But how about the following:
If rendering the plot is the time-consuming part of your code, you may try generating plot points for all circles into the same X,Y arrays and calling plot() once at the end. Intead of the rectangle function, each circle can be a set of enough number of points which you can calculate using the circle equation.