How to check if all the data in the cell array are the same?

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There is a variable called 'data'
in a cell array of 1x10
{100} {100} {100} {100} {100} {100} {100} {100} {100} {100} 100 has the same value.
How can I return these 10 data to True or False?
isequal(data(1),data(2),data(3),data(4),data(5),data(6),data(7),data(8),data(9),data(10))
Instead of writing down all the elements like this, I want to make sure that all the data in th
e cell array has the same value even if the size of the cell array changes.

Answers (3)

Stephen23
Stephen23 on 21 Mar 2022
Edited: Stephen23 on 21 Mar 2022
The simple and very efficient MATLAB approach is to use a comma-separated list:
Avoid approaches which join the data together (e.g. CELL2MAT) or that change data type (e.g. to STRING): they are inefficient, fragile, and will fail for arrays of incompatible sizes, types, or due to loss of information when converting type.
C = repmat({10},1,9)
C = 1×9 cell array
{[10]} {[10]} {[10]} {[10]} {[10]} {[10]} {[10]} {[10]} {[10]}
X = isequal(C{:})
X = logical
1
C{1} = 10+eps(10)
C = 1×9 cell array
{[10.0000]} {[10]} {[10]} {[10]} {[10]} {[10]} {[10]} {[10]} {[10]}
X = isequal(C{:})
X = logical
0

Chunru
Chunru on 21 Mar 2022
c = {100, 100, 100, 200} % cell array
c = 1×4 cell array
{[100]} {[100]} {[100]} {[200]}
cm = cell2mat(c);
same = all(cm == cm(1))
same = logical
0

Arif Hoq
Arif Hoq on 21 Mar 2022
if you want to find every index for true or false
A={100};
B=repmat(A,1,10);
[Lia Locb]=ismember(string(B),string({100}))
Lia = 1×10 logical array
1 1 1 1 1 1 1 1 1 1
Locb = 1×10
1 1 1 1 1 1 1 1 1 1
  1 Comment
Jan
Jan on 21 Mar 2022
The conversion to a string is an expensive indirection. isequal(A{:}) is faster.

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