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# Values closest to a number

Asked by cfjunior on 27 Apr 2013

How do I find the two closest numbers from a number in a vector column? For example, suppose I have:

A = [2 3 5 6 9 10 23 45 100]';

If the number I'm seaching is 7, my requested answer would be 6 and 9.

## 1 Comment

proecsm on 27 Apr 2013

why wouldn't it return 5 & 6? 5 is as close as 9

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Answer by Wayne King on 27 Apr 2013
Edited by Wayne King on 27 Apr 2013

It looks like you are looking for the closest numbers where one is below 7 and one is above. If that is the case.

```    A = [2 3 5 6 9 10 23 45 100]';
num = 7;
closest_below = max(A(A<num));
closest_above = min(A(A>num));```

because otherwise, 5 is just as close to 7 as 9 is.

## 1 Comment

cfjunior on 27 Apr 2013

Yes, thats what I need!! Thanks a lot!!

Answer by the cyclist on 27 Apr 2013

There are many possible ways to do this. Here is one way.

```A = [2 3 5 6 9 10 23 45 100]';
```
```v = 7;
```
```idx_hi = find(A>7,1,'first');
```
```twoClosest = A([idx_hi-1,idx_hi])
```

I assumed that your A vector was sorted, that all values are unique, etc. You want to be careful if these conditions are not met.