looking for equivalent in MATLAB of "where variable1 in ('a', 'b','c')" in SQL

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Binzi Shu 2016-2-18

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回答： Arnab Sen 2016-2-22

new to matlab. If I'm in SQL I would write "select ... where variable1 in ('a', 'b','c')". How does that translate in to matlab syntax? Thanks.

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jgg 2016-2-18

Probably ismember is the function you want? I don't know SQL very well, but if you want to select or check whether a variable is a member of a set you can use this or find.

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Answer 1

Arnab Sen 2016-2-22

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Hi Binzi,

I understand from the query that you have two arrays and you would like to find out the elements in the first array which is also present in the second array.

You may use the function 'ismember' for this purpose.

You may refer to the following code snippet:

>>Variable1=[ 'b','e','a']; >>B=['a','b','c']; >>[Lia,Locb] = ismember(Variable1,B) Variable 'Lia' returns logical 1 for each match and 'Locb' returns the index of the elements in 'B' for each match.

You can use 'find' function to get the index in 'Variable' for matching elements as below.

>>A=find(Lia);

For more details about 'ismember', refer to the following link: http://www.mathworks.com/help/matlab/ref/ismember.html