HP, SP, Agi based on Str Dex and Int

[S0L0]

Hi there

I want to make my project work as a real RPG, wich means, the:
Strenght = Affect the damage delt by weapons, the Max HP and Physical Defense
Dexterity = Affect the agility and attack rate (so Agility get removed from menus)
Intelligence = Affect the damage delt by spells, the Max SP, and Magic Defense


So this would mean, I can get a better custumization for each actor, and not the so static-level up, If i'm making a:
Warrior: I would focus on Strenght for be stronger and get more HP
Wizard: I'll focus on Intelligence for get more MP aka SP (mana points), deal more damage spells and also better magidc defense
Ranger: I would focus on the Dextery wich would give better attack rate so better dmg with the range attacks


I'm requesting this because I tried edit myself the forumla of MaxHP into this:

  def maxhp
    n = [[[base_maxhp + @maxhp_plus]*[$data_actors[@actor_id].parameters[2, @level]], 1].max, 9999].min
#    n = [[base_maxhp + @maxhp_plus, 1].max, 9999].min
    for i in @states
      n *= $data_states[i].maxhp_rate / 100.0
    end
    n = [[Integer(n), 1].max, 9999].min
    return n
  end

"Can't convert Array into Integer" and I relay not sure what i'm doing wrong, I even tried using direct forumla like the $game_party[0].str for test the max HP based on the Strenght of party leader

Every help will be apreciated, thanks