index.m - create a list of the indices and values of an array

Create a list where each value (content) of an array is displayed together with its index.

Description

This function displays each value of an array together with its index. It is possible to ignore zeros and/or NaNs and/or to sort the list according to value. The values can be integers or floating point numbers.

EXAMPLES:

>> a=[2,3,NaN;1,2,4;7,0,9];

>> index(a,'sorted')

ans =
     3 2 0
     2 1 1
     1 1 2
     2 2 2
     1 2 3
     2 3 4
     3 1 7
     3 3 9
     1 3 NaN

>> index(a,'sorted','nonans','nozeros')

ans =
     2 1 1
     1 1 2
     2 2 2
     1 2 3
     2 3 4
     3 1 7
     3 3 9

• MATLAB release: MATLAB 7.5 (R2007b)

[Jos x@y.z]

I suggest you look at IND2SUB, which allows for easy vectorization
% START OF CODE
a = [3 2 1 ; 7 0 1 ; NaN -1 Inf] ; % some data
[ind{1:ndims(a)}] = ind2sub(size(a),1:numel(a)) ;
r = [cat(1,ind{:}).' a(:)]
% END OF CODE
  
and work from that onwards ...
On the good side, at least you provided some help, but take care of a proper H1 line used by LOOKFOR.

[Georg Stillfried]

Thank you Jos. Your suggestion is now incorporated in an improved version.