vectorization of ismember function

Question

0 个投票

Hello, I am interested in using the ismember function for strings by row with out using a for loop. For example I would have

A = {'cat','dog','bird'}

as my input vector and

B = {'cat','dog';'dog','bird'}

using ismember in a for loop

 for k = 1:2
 M(k,:) = ismember(A,b{k,:});
 end

would return the matrix;

M = [1 1 0 ; 0 1 1].

Right now I have this written in a for loop but I was wondering if there is a way to do it without one. Thank you in advance.

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Answer 1

Andrei Bobrov 2013-6-8

编辑：Andrei Bobrov 2013-6-8

0 个投票

M = cell2mat(arrayfun(@(ii)ismember(A,B(ii,:)),(1:size(B,1))','un',0));

or

[~,b] = ismember(B,A);
M = accumarray([repmat((1:size(b,1))',size(b,2),1),b(:)],1);

Ryan 2013-6-8

Thank you!