Euclidean distance between two vectors (single row matrix)

matlab, octave

Solution

diff = A - B;
distance = sqrt(diff * diff');

or

distance = norm(A - B);

Problem

I have two vectors (single row matrices). Assume that we already know the length `len`. ``` A = [ x1 x2 x3 x4 x5 .... ] B = [ y1 y2 y3 y4 y5 .... ] ``` To calculate Euclidean distance between them what is the fastest method. My first attempt is: ``` diff = A - B sum = 0 for column = 1:len sum += diff(1, column)^2 distance = sqrt(sum) ``` I have loop through this methods millions of times. So, I am looking for something which is fast and correct. Note that I am not using MATLAB and don't have pdist2 API available.

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