my code become busy for euclidean distance

1 次查看（过去 30 天）

fatemeh 2014-2-9

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/115411-my-code-become-busy-for-euclidean-distance

评论： Walter Roberson 2014-2-9

i write code for euclidean distance in nested for like this:

for rsize=1:tests
  for k=1:ts
    dis(k,1)=  pdist2( testset(rsize,1:57),tmatrix(k,1:57),'euclidean');
  end
end

its run time is very long 1-2 hours why? how can i correct this code?

4 个评论
显示 2更早的评论隐藏 2更早的评论

Roger Stafford 2014-2-9

The point I am making, Fatemeh, is that if you actually need the output of 'pdist2' for each possible combination of values of 'rsize' and 'k', it should be possible to quickly extract it in an appropriate manner from that single "maximum" run, rather than having to go through 'pdist2' calls repeatedly. Doing it that way should save a lot of time if you do it right. That "maximum" run contains all the pairs that you will need.

In all this discussion I am assuming that the matrices 'testset' and 'tmatrix' remain unchanged for each computation of 'pdist2', except that different portions of each are used. Is that correct? Otherwise the code you have shown wouldn't make sense.

fatemeh 2014-2-9