# Notation: getting one value from arg max

1. Apr 6, 2015

### Max.Planck

I want to take the arg max over a number of functions as below, however it is possible that there are multiple i's for which the result is maximal. How do i denote that I want to take the last possible i, for example if it results in 3 and 5 I want it to return 5, is there notation available for this?

$arg\,max_{i} f_{i}(\mathbf{x})$

2. Apr 6, 2015

### wabbit

I am not aware of such notation, but it's unclear to me whether you're looking to denote $$argmax f\text{ where }f(x)=max_{\{i\}}f_i(x)$$ or $$max_{\{i\}} argmax f_i$$

3. Apr 6, 2015

### Max.Planck

I want to get the index of the function with the highest value for that particular x, and if there are several, the last index should be returned.

4. Apr 6, 2015

### wabbit

OK, so $\max(\text{argmax}_{i}f_i(x))$... Sorry, can't think of a standard notation for that, maybe others will.