Average distance from the origin

matrix=load('Data');
x = matrix(:,1);
y = matrix(:,2);
distances = sqrt((x-0).^2 + (y-0).^2)
sum(distances)./(size(matrix))

Hey, so I just wanted to make sure I'm doing this correctly. What I'm trying to do is find the average distance between points in a matrix and the origin. I got an answer I'm not quite sure about being correct, so I wanted to be safe.

Answer 1

[Star Strider]

You seem to be doing it correctly, but if you can use the built-in functions, I would use hypot and mean:

distances = hypot(x,y);
avg_dist = mean(distances);

[TS]

Oh! Thank you! I completely forgot that there were built in functions for this!

[Star Strider]

My pleasure!

Answer 2

[Chad Greene]

Looks right, but you could write it more simply:

matrix=load('Data');
x = matrix(:,1);
y = matrix(:,2);
distances = hypot(x,y); 
mean(distances)

[Chad Greene]

Also, plot the data and verify for yourself.

plot(x,y,'bo')

circles(0,0,mean(distances),'facecolor','none)