how to use if condition in array variables?

The syntax

PHP Code:

'amt' => if($certid=1,8500 else 300 , 


is wrong in every aspect (only one bracket, a comma at the wrong place, a single equal sign, etc.). It would certainly fail to get one value or another, based on a condition.

Yeah. Well. There is that.
Forgive me for trying to add an explanation to your terse (and entirely correct) reply.