# Return index of cell in a cell array for which contains a desired element

3 views (last 30 days)
hmhuang on 20 Feb 2022
Commented: Voss on 20 Feb 2022
I have a cell array:
C = {[1,2,4], [3,5], [8,9]}
I would like to have a function, such that:
somefunc(C, 2) % will return 1, indicating that 2 is in the 1st cell of the cell array
somefunc(C, 8) % will return 3, indicating that 8 is in the 3rd cell of the cell array
somefunc(C, 7) % will return 0 or -1 or whatever that is not 1 or 2, or 3
Is there any MATLAB built-in function that could achieve this purpose?
(Assume the elements in the cell array are unique.)

Voss on 20 Feb 2022
C = {[1,2,4], [3,5], [8,9]};
find(cellfun(@(x)ismember(2,x),C))
ans = 1
find(cellfun(@(x)ismember(8,x),C))
ans = 3
find(cellfun(@(x)ismember(7,x),C))
ans = 1×0 empty double row vector
Voss on 20 Feb 2022
Or, making that command into a function you can call:
C = {[1,2,4], [3,5], [8,9]};
find_cell_containing(C,2)
ans = 1
find_cell_containing(C,8)
ans = 3
find_cell_containing(C,7)
ans = 1×0 empty double row vector
function idx = find_cell_containing(C,in)
idx = find(cellfun(@(x)ismember(in,x),C));
end