How to check if one vector is a subset of another?

Question

I'm looking for a matlab way of doing this. Looping through seems easy enough. I have two vectors, say `a = [1 2 3]` and `b = [1 54 2 4 6 3]`. I want to determine if `a` is a subset of `b`. How is this done?

Accepted Answer

Probably the easiest and quickest way to do this is to use the functions ISMEMBER and ALL:

```
isSubset = all(ismember(a, b));
```

You can also use SETDIFF and ISEMPTY, but this appears to be less efficient (it runs a little slower than the above in R2010b):

```
isSubset = isempty(setdiff(a, b));
```

How to check if one vector is a subset of another?

Solution

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