Calculating arc length of segments using interparc

Hi, I was using 'interparc' function to divide an arc in to 'n' number of equal segments. I expected each segment to give me equal arc length. But when i calculate the arc-length of each one of these segments, i am getting different arc-lengths. Any explanation regarding this will be appreciated?

'px','py' and 'arc_pt' files are attached as references

px  = X_coord_req;
py  = Y_coord_req;
pt = interparc(50,px,py,'linear');
plot(px,py,'r',pt(:,1),pt(:,2),'b-o') 
ax = gca;
ax.YDir = 'reverse';
axis([0 6600 0 5000])
arc_pt  = zeros(length(pt)-1,1);
n = length(pt(:,1));
for ii = 1:n-1
    arc_pt(ii) = sqrt((pt(ii+1,1) - pt(ii,1))^2 + (pt(ii+1,2) - pt(ii,2))^2);
end

[KSSV]

interparc is not an inbuilt function........you need to attach that.

[KSSV]

Okay got it from the file exchange: https://in.mathworks.com/matlabcentral/fileexchange/34874-interparc

[Hari krishnan]

@KSSV. Apologies. Its the same function you attached above