TITLE: what argmax means?
QUESTION [11 upvotes]: my main problem is that, i don't understand what argmax means in this equation (page 134., figure 4., the output part)
I want to write a code, but i don't understand this equation. Is there any simpler form of this equation ? (maybe an example)
This is how i understand it:
1. i count the sum first
2. i find the argmax 
Sorry for my dummy question, but i am not realy good in this area.
Thanks for your answers !

REPLY [3 votes]: In general $$x^*=\arg \max_x f(x) $$ means return $x$ that maximizes $f(x)$. 
How to find $x^*$? 1) Find $f(x)$ for all possible values of $x$ as $\{x_n,\,f(x_n)\}$. 2) Find the maximum value of $f(x)$ in the set $\{f(x_n)\}$, let's denote it by $f(x_\max)$. 3) return $x_\max$. 
You don't have to store all values. You can start by saying that $x_\max=x_1,\,f_\max=f(x_1)$. Then if $f(x_2)>f_\max$ update the values as $x_\max=x_2,\,f_\max=f(x_2)$. If not, keep the previous values. When all the possible values of $x$ are considered, your $x_\max$ at the end will be the value you are looking for.
Apply this to your situation.