MATLAB: Indexing for cell arrays

Question

I have 10×1300 cell array z, how do i find a certain value of z using indexing

find(abs(z-z_position)<intvl) did not work

and how do i do the opposite as well? eg. z{1,1}(1)

A portion of z, z value is random for each cell.
Columns 1296 through 1300
      [1×23 double]    [1×23 double]    [1×29 double]    [1×23 double]    [1×25 double]
      [1×27 double]    [1×25 double]    [1×25 double]    [1×25 double]    [1×27 double]
      [1×21 double]    [1×25 double]    [1×27 double]    [1×27 double]    [1×25 double]
      [1×27 double]    [1×29 double]    [1×29 double]    [1×25 double]    [1×23 double]
      [1×27 double]    [1×25 double]    [1×23 double]    [1×27 double]    [1×27 double]
      [1×27 double]    [1×27 double]    [1×23 double]    [1×21 double]    [1×23 double]
      [1×25 double]    [1×29 double]    [1×27 double]    [1×27 double]    [1×27 double]
      [1×27 double]    [1×21 double]    [1×21 double]    [1×29 double]    [1×27 double]
      [1×25 double]    [1×25 double]    [1×25 double]    [1×21 double]    [1×27 double]
      [1×23 double]    [1×25 double]    [1×25 double]    [1×25 double]    [1×23 double]

Answer 1

cellfun( @(Z) find(abs(Z-z_position)<intvl), z, 'uniform', 0)

the output will be a cell array each element of which is the list of indices for the corresponding cell in z.