help ismember % 'row' option
ISMEMBER True for set member.
LIA = ISMEMBER(A,B) for arrays A and B returns an array of the same
size as A containing true where the elements of A are in B and false
otherwise.
LIA = ISMEMBER(A,B,'rows') for matrices A and B with the same number
of columns, returns a vector containing true where the rows of A are
also rows of B and false otherwise.
[LIA,LOCB] = ISMEMBER(A,B) also returns an array LOCB containing the
lowest absolute index in B for each element in A which is a member of
B and 0 if there is no such index.
[LIA,LOCB] = ISMEMBER(A,B,'rows') also returns a vector LOCB containing
the lowest absolute index in B for each row in A which is a member
of B and 0 if there is no such index.
The behavior of ISMEMBER has changed. This includes:
- occurrence of indices in LOCB switched from highest to lowest
- tighter restrictions on combinations of classes
If this change in behavior has adversely affected your code, you may
preserve the previous behavior with:
[LIA,LOCB] = ISMEMBER(A,B,'legacy')
[LIA,LOCB] = ISMEMBER(A,B,'rows','legacy')
Examples:
a = [9 9 8 8 7 7 7 6 6 6 5 5 4 4 2 1 1 1]
b = [1 1 1 3 3 3 3 3 4 4 4 4 4 9 9 9]
[lia1,locb1] = ismember(a,b)
% returns
lia1 = [1 1 0 0 0 0 0 0 0 0 0 0 1 1 0 1 1 1]
locb1 = [14 14 0 0 0 0 0 0 0 0 0 0 9 9 0 1 1 1]
[lia,locb] = ismember([1 NaN 2 3],[3 4 NaN 1])
% NaNs compare as not equal, so this returns
lia = [1 0 0 1], locb = [4 0 0 1]
Class support for inputs A and B, where A and B must be of the same
class unless stated otherwise:
- logical, char, all numeric classes (may combine with double arrays)
- cell arrays of strings (may combine with char arrays)
-- 'rows' option is not supported for cell arrays
- objects with methods SORT (SORTROWS for the 'rows' option), EQ and NE
-- including heterogeneous arrays derived from the same root class
See also ISMEMBERTOL, INTERSECT, UNION, UNIQUE, UNIQUETOL, SETDIFF,
SETXOR, SORT, SORTROWS.
Documentation for ismember
doc ismember
Other functions named ismember
categorical/ismember duration/ismember sym/ismember
cell/ismember gpuArray/ismember tabular/ismember
dataset/ismember mtree/ismember tall/ismember
datetime/ismember