PokerTracker

Hello. I took "VP$IP /opps" stat from repository and decided to make stats by position using it as a template. I started with VPIP UTG.
First, I made an action column, which is the number of times when player voluntarily put money in the pot from UTG -

cnt_vpip_utg = sum(if[holdem_hand_player_statistics.flg_vpip AND holdem_hand_player_statistics.position = 3, 1, 0])

Second, I made an opportunity column, which is the number of times when player had the opportunity to voluntarily put money in the pot from UTG -

cnt_vp_utg_opp = sum( if[ NOT(lookup_actions_p.action='') AND holdem_hand_player_statistics.position = 3, 1, 0 ] )

After that I made this - VP$IP UTG = (cnt_vpip_utg / cnt_vp_utg_opp) * 100

I put this expression in the popup and the next to it I put usual VP$IP stat with checking EP (early position) and showing Times/Opportunities True. I though everything will be fine, but I got different numbers both for actions and opportunities. And the same with other positions. Why is that? Where is my mistake, if it is? By the way, could you translate to me, please, what does it mean - NOT(lookup_actions_p.action='')

Your expressions look good, but EP does not only count position 3 off the button - there can be other seats included too.
You can see which numeric positions are defined as EP/MP/LP in the tutorial: Statistic Properties.

NOT(lookup_actions_p.action='')
..means that the preflop actions string is not empty. In English, that means that the player made at least one action of some kind, meaning that they chose whether or not to VPIP.

WhiteRider wrote:...EP does not only count position 3 off the button - there can be other seats included too.

Ok, I got it. In order to see what range of hands someone plays when he enters the pot at the first seat of the table, I also have to know how many players seat at that table. By this I can define which numeric positions I should use. Right? So, my next question - How to set the number of players at the table?

holdem_hand_summary.cnt_players = X

Change X to whatever number you want.