Math Optimization

[~GaLs~]

I'm bad in math, how should I optimize this code?

private function GetDumLvlFrmDist takes real dist return integer
if dist <= 200 then
    return 1
elseif dist >200 and dist <= 400 then
    return 2
elseif dist >400 and dist <= 600 then
    return 3
elseif dist >600 and dist <= 800 then
    return 4
elseif dist >800 and dist <= 1000 then
    return 5
elseif dist >1000 and dist <= 1200 then
    return 6
elseif dist >1200 and dist <= 1400 then
    return 7
elseif dist >1400 and dist <= 1600 then
    return 8
elseif dist >1600 and dist <= 1800 then
    return 9
elseif dist >1800 and dist <= 2000 then
    return 10
endif
endfunction

 

[AceHart]

return 1 + R2I(distance) / 200

Not exactly the same though, it excludes the next upper limit.
Though I guess that's not needed anyway.

 

[~GaLs~]

Ace, sorry but I can't use yours.

Lets start with an example.
If the dist is 1000.

It should return 5 as shown in my code.
But if it is in your equation, it would return 6.

1 + R2I(1000) / 200
= 1 + 1000 / 200
= 1 +5
= (6)

*Hope I didn't left out something

 

[saw792]

return 1 + R2I(distance - 1) / 200

Problem solved.

 

[AceHart]

> It should return 5 as shown in my code.

No, it shouldn't.
If it did, the distribution wouldn't be uniform anymore as the lowest interval has one more choice than the others.


Though, if you insist:
return (R2I(distance) + 199) / 200

 

[~GaLs~]

>>If it did, the distribution wouldn't be uniform anymore as the lowest interval has one more choice than the others.
What does this means?

 

[saw792]

Well, range 0-200 has 201 members, 201-400 has 200, 401-600 had 200, etc.

 

[~GaLs~]

>>Well, range 0-200 has 201 members, 201-400 has 200, 401-600 had 200, etc.
Hmm, ok, thanks for the point. I get it now.

But it is impossible for a player to cast spell target with 0 dist from the caster, right?
So, I should put it as, 1 - 200, and not 0 - 200.

For this reason, I simply put if dist <= 200 then without specified the smallest value.

 

[Flare]

But it is impossible for a player to cast spell target with 0 dist from the caster, right?

You can click the caster's portrait when the target indicator appears, and it should be 0 distance (since the distance between the caster's location and the caster's location is 0, presumably )