Calculating efficiently the euclidean distance

Question

Riccardo Tronconi 2021-7-19

评论： Riccardo Tronconi 2021-7-19

Hi guys I would like to calculate the euclidean distance without a for loop to speed up my running time.

I have a timetable A as input with m-rows and 4 columns:

1st column: X point 1

2nd column: Y point 1

3rd column: X point 2

4th column: Y point2

Now I loop over each row of the timetable and I use norm( A(i, 1:2) - A(i, 3:4)). Of course the output should be mx1.

Is there a more efficient way to compute this operation?

Answer 1

Matt J 2021-7-19

编辑：Matt J 2021-7-19

In recent Matlab, you can just do,

vecnorm(A(:, 1:2) - A(:, 3:4),2,2);

In less recent Matlab, you can do,

sqrt(sum( (A(:, 1:2) - A(:, 3:4)).^2,2))

thanks a lot!!! :)