Chief Delphi - [TBA]: Incorrect qual points

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[TBA]: Incorrect qual points

Seems like TBA is incorrectly calculating the district qual points for each event. I'm not sure if its been noticed or if a fix is in the works or what TBA is even coded in, but I was messing around in php and got it running. If you'd like to steal the code and port it over to whatever you guys use, works for me.

PHP Code:


		
			
function qual_points($n, $r){

        $a=1.07;

        return ceil((inverf(($n-(2*$r)+2)/($a*$n))*(10/(inverf(1/$a))))+12);

    }

    

    function sign($number) {

        return ( $number > 0 ) ? 1 : ( ( $number < 0 ) ? -1 : 0 );

    }

    

    function inverf($x) {

        $a=0.147;

        return sign($x)*sqrt(sqrt(pow(((2/(pi()*$a))+((log(1-pow($x, 2)))/2)), 2) - ((log(1-pow($x, 2)))/$a) )-((2/(pi()*$a))+(log(1-pow($x, 2)))/2));

    }

*credit to my bro paul for some help

called with qual_points(n,r) where n=the number of teams at the event and r=rank

the formula I'm using for inverf(x) comes from an approximation found on wikipedia

These incorrect calculations currently up are messing with a project I'm currently working on with the API, so I don't know if there is anything else I can do to help sort it out but please let me know.

Re: [TBA]: Incorrect qual points

Thanks for the reminder on this. TBA is written in python, and has an open issue for it. We'll get it corrected soon

Re: [TBA]: Incorrect qual points

Thanks. Our inverse error function indeed gets points off by 1 sometimes.

Re: [TBA]: Incorrect qual points

it is off by as much as 3 points in many places.

Re: [TBA]: Incorrect qual points

Converted over to python by a friend

Code:

def sign(x):

    if x > 0:

        return 1

    elif x < 0:

        return -1

    else:

        return 0



def inverf(x):

    a = 0.147

    formula = math.sqrt((math.sqrt((((2 / (math.pi * a)) + ((math.log(1 - x**2)) / 2))**2) - ((math.log(1 - x**2)) / a))) - ((2 / (math.pi * a)) + (math.log(1 - x**2)) / 2))

    return formula*sign(x)



def qual_points(n, r):

    a = 1.07

    formula = math.ceil((inverf((n-(2*r)+2)/(a*n))*(10/(inverf(1/a))))+12)

    return formula