find length of a line use 2 dots

Question

Rahma Yeni 2012-3-23

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/33215-find-length-of-a-line-use-2-dots

Hello.. I have code like this

x = [0.2177, 0.6302, 0.9597, 0.6025];
y = [0.4284, 0.7822, 0.5073, 0.1564];
for m = 1:length(x)
    for n = 1:length(x)
 (n)= sqrt((x(:,n+m) - x(:,n)).^2 + (y(:,n+m) - y(:,n)).^2)
    end
end
pjgtot = sum(pjg)

and the result are:

pjg =
      0.5434
pjg =
      0.5434    0.4291
pjg =
      0.5434    0.4291    0.5007
??? Attempted to access x(:,5); index out of
bounds because size(x)=[1,4].
Error in ==> maze_solution at 322
        pjg (n)= sqrt((x(:,n+m) - x(:,n)).^2 +
        (y(:,n+m) - y(:,n)).^2)
>>

the result is true, that is :

pjg = 0.5434 0.4291 0.5007

but it give some error too.. why it happened .. is there something wrong with my code..?? manual calculations to obtain these results is (in this example, i use x = 0.2177, 0.6302, and y = 0.4284, 0.7822)

pjg = sqrt((0.6302-0.2177)^2 + (0.7822-0.4284)^2)

where is the fault..??

thank you.. :)