how to calculate distance ?

I want to calculate the distance between two points of an edge there is my code

{
clc
clear all
close all
I = imread('C:\Users\PC\Pictures\matlab.bmp');
imshow(I)
BW = im2bw(I);
imshow(BW)
dim = size(BW)
col = round(dim(2)/2)-90;
row = min(find(BW(:,col)));
boundary = bwtraceboundary(BW,[row, col],'N');
imshow(I)
hold on;
plot(boundary(:,2),boundary(:,1),'g','LineWidth',3);
}

can someone help me

Answer 1

[Image Analyst]

Use bwboundaries(), not bwtraceboundary(). Then, what 2 points do you want the distance between? Why can't you just use hypot()?