c de math.h kullanmadan kök alma

 
  // tert kok alma islemini yapar. Kodun orjinalini bozmamak icin yeni bir fonksiyon yazdim asagida. 
  // 1 / sqrt(f) islemini yapar. 
  float Q_rsqrt( float number ) 
  { 
  	long i; 
  	float x2, y; 
  	const float threehalfs = 1.5F; 
    
  	x2 = number * 0.5F; 
  	y  = number; 
  	i  = * ( long * ) &y;                       // evil floating point bit level hacking 
  	i  = 0x5f3759df - ( i >> 1 );               // what the fuck? 
  	y  = * ( float * ) &i; 
  	y  = y * ( threehalfs - ( x2 * y * y ) );   // 1st iteration 
  //      y  = y * ( threehalfs - ( x2 * y * y ) );   // 2nd iteration, this can be removed 
    
  	return y; 
  } 
   
  // bu fonksiyon istenilen sqrt(f)'i doner. 
  float fast_sqrt(float f) { 
      return 1 / Q_rsqrt(f); 
  }