# How to compare two logical arrays

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Rhiannon Jones on 6 Jun 2019
Commented: Rhiannon Jones on 6 Jun 2019
Hi,
I would like to compare two logical cell arrays, creating a third logical cell array returning true for when index values of both logical cell arrays are true.
My error;
Undefined unary operator '~' for input arguments of type 'cell'.
Is there a way to do this for cell?
Many thanks
% the two different logical arrays produced by cellfun:
fun_stf_p = cellfun(@(x) x >= stf_p_lb & x <= stf_p_ub, PRES, 'UniformOutput', false);
fun_stf_s = cellfun(@(x) x >= stf_s_lb & x <= stf_s_ub, PSAL, 'UniformOutput', false);
% Create a third logical cell array for which both cell arrays return true
fun_stf = ~fun_stf_p & ~fun_stf_s; % doesn't work
Edited: Adam on 6 Jun 2019
Why do you have logical cell arrays in the first place? If they have to be the same length (which they do for you to compare them element by element) and they are both logical then why not just put them in a logical array and use
c = a & b;
type of logic? Surely you don't need the 'UniformOutput', 'false' if the two arrays fulfil those criteria.
Rhiannon Jones on 6 Jun 2019
Both cell arrays are a series of double arrays which match in dimension between the cell arrays, but change size within the cell array.

Matthew Sisson on 6 Jun 2019
Edited: Matthew Sisson on 6 Jun 2019
One option is to continue using cellfun for this, as follows:
fun_stf = cellfun(@(x,y) ~x & ~y,fun_stf_p,fun_stf_s)
Another option is to convert to a double and then back again. Is there a reason why you are using cell arrays in the first place? If vectors are all the same length, working with logical arrays will be easier & faster.
Rhiannon Jones on 6 Jun 2019
Thanks for your answer! Both cell arrays are a series of double arrays which match in dimension between the cell arrays, but change size within the cell array.
This code returns logical true for when both cells are 0 or 1. I only want it to return logical true when they both satisfy the conditions and return logical true. Sorry if that wasn't clear.
Rhiannon Jones on 6 Jun 2019
I'm guessing this would be x==1 & y==1 instead of ~x & ~y, which seems to be working