Distance formula

[rlnd1]

Hi

I'm reviewing the method used for calculating distances between points in the ccep_retrieveInterROIDistance.m function, specifically at this line:
ccep_retrieveInterROIDistance.m, Line 73.

It seems the calculation sums all components and then applies the square root. For me, this order would make more sense:

1. calculate difference between x, y, z-coordinates of neighbouring points
2. square the difference
3. sum the three components
4. apply square root to get the distance between all neighbouring points
5. sum all individual distances to get the total distance

Thank you and all the best,
Roland