Develop
2013.10.31 16:51
[ios] Random Thoughts: Rand() vs. arc4random()
조회 수 68033 댓글 0
랜덤함수 사용시..
iOS
There are several built-in randomizers on the iPhone, and most people's first thought is to use rand() after seeding it by calling
srandom(time(NULL));
But... rand() is really not a very good PRNG. random() is a little better, but still less then ideal. Fortunately, these are not the only ones available on the iPhone. Personally, I like arc4random() because it's a decent pseudo-random algorithm and has twice the range or rand().
On the iPhone, RAND_MAX is 0x7fffffff (2147483647), while arc4random() will return a maximum value of 0x100000000 (4294967296), giving much more precision. You also don't need to seed arc4random(), as the first call to it automatically seeds it.
결론은 arc4random() 을 사용하자.
[출처] http://iphonedevelopment.blogspot.com/2008/10/random-thoughts-rand-vs-arc4random.html
-
[ios] UI컨트롤러 샘플코드
-
[ios] 최신 UI 모음.. (나중에 정리할 것)
-
아이 훌레시 작업중 ㅋㅋ
-
[ios] 앱에서 다른 앱 실행시키기
-
[ios] None IB vs. StoryBoard 샘플 소스
-
[python] 애니팡, 캔디팡 매크로
-
[ios] Hybrid 앱 스터디 발표 자료
-
[ios] 간단한 방법으로 OS버전 확인하기.
-
[ios] UIView에서 상위 UIViewController 가져오기
-
[ios] GCD 변수 사용 예제
-
[ios] UIAlertView 초간단 샘플 ㅎㅎ
-
[ios] Random Thoughts: Rand() vs. arc4random()
