matrix - How to find x number of closest neighbours matching criteria in MATLAB? -


i have m*n matrix values of 0-9. basically, want able find cells have 0 value , find k closest neighbours aren't 0.

my code right along lines of this:

  • locate cells 0 , make a*2 matrix holding x , y locations

  • do same cells without 0

  • make loop cycles through each given 0 coordinate , measure distance every non-zero cell , record in row 1 of new matrix (row 2 , 3 x , y coordinates, respectively)

  • use sortrows() matrix in ascending order , extract first k values (ie, closest k number of coordinates)

  • repeat

what hoping more along lines of finding k closest non-zero cells without internal loop , repeating each 0 cell. advice appreciated, much.

i solve problem finding nonzero entries, e.g. doing, , determining corresponding vertices. can use dsearchn find k nearest points. if want repeatedly, benefit constructing delaunaytriangulation object.


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