weird shape of ROC for my data

this is the code that results in generating ROC for my data. i have attached my roundMeas matrix. the problem is that my ROCs look really strange. they are not actually like curves. and i don't know what is wrong. i also don't know anything about setting thresholds for plotting ROC. can any body help?

TPRvect=zeros(27,300); FPRvect=zeros(27,300); u=13; for e=1:6 for i=1:27 for j=1:300 xx=roundMeas(j,3,e); TPRvect(i,j)=xx{1,1}(i); yy=roundMeas(j,6,e); FPRvect(i,j)=yy{1,1}(i); end end for i=1:27 qq=TPRvect(i,:); ww=FPRvect(i,:); figure (u) plot(ww,qq) xlabel('FPR') ylabel('TPR') str=sprintf('ROC of class %d for clustering%d', i, e); title(str) h=figure(u); saveas(h,sprintf('FIG%d.jpeg',u)) u=u+1; end e=e+1; end