MATLAB Function Reference |
Syntax
Description
tf = ismember(A, S)
returns a vector the same length as A
, containing logical 1
(true
) where the elements of A
are in the set S
, and logical 0
(false
) elsewhere. In set theory terms, k
is 1 where A
S
. A
and S can be cell arrays of strings.
tf = ismember(A, S, 'rows'),
when A
and S
are matrices with the same number of columns, returns a vector containing 1
where the rows of A
are also rows of S
and 0
otherwise. You cannot use this syntax if A
or S
is a cell array of strings.
[tf, loc] = ismember(A, S, ...)
returns index vector loc
containing the highest index in S
for each element in A
that is a member of S
. For those elements of A
that do not occur in S
, ismember
returns 0
.
Examples
set = [0 2 4 6 8 10 12 14 16 18 20]; a = reshape(1:5, [5 1]) a = 1 2 3 4 5 ismember(a, set) ans = 0 1 0 1 0 set = [5 2 4 2 8 10 12 2 16 18 20 3]; [tf, index] = ismember(a, set); index index = 0 8 12 3 1
See Also
issorted
, intersect
, setdiff
, setxor
, union
, unique
, is*
islogical | ismethod |
© 1994-2005 The MathWorks, Inc.