Clear Filters
Clear Filters

pdist2 output is larger than expected

3 views (last 30 days)
X= pdist2 (A,B, "chebychev")
A and B both are 3000x3 arrays (x,y,z data).
Why is X a 3000x3000 array rather than a 3000x1 array?
This seems to give the right answer though... why?
Z =diag(pdist2 (A,B, "chebychev"));

Accepted Answer

Dave B
Dave B on 15 Nov 2021
pdist2 is providing all the pairwise distances. It compares row 1 of A with row 1 of B (Z(1,1)), then row 1 of A with row 2 of B (Z(1,2) and Z(2,1)), etc. Along the diagonal are the matching row cases.
  3 Comments
Dave B
Dave B on 15 Nov 2021
Edited: Dave B on 15 Nov 2021
Chebyshev distance is the maximum distance across dimensions, right?
a=rand(10);
b=rand(10);
cheby_pdist2=diag(pdist2(a,b,'chebychev'))
cheby_pdist2 = 10×1
0.8386 0.6272 0.8585 0.6400 0.4895 0.8044 0.6681 0.7439 0.8985 0.7146
cheby_daveb=max(abs(a-b),[],2)
cheby_daveb = 10×1
0.8386 0.6272 0.8585 0.6400 0.4895 0.8044 0.6681 0.7439 0.8985 0.7146

Sign in to comment.

More Answers (0)

Categories

Find more on Statistics and Machine Learning Toolbox in Help Center and File Exchange

Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!