// Newtons approximation to the square root
val _sqrt = { flt x ->
    flt guess = x;
    while( 1 ) {
        flt next = (x/guess + guess)/2;
        if( next == guess ) return guess;
        guess = next;
    }
};
flt farg = arg;
return _sqrt(farg) + _sqrt(farg+2.0);