random

问题 I am generating tokens for users in PHP when they register. I am wondering if two users could ever get the same token... as this will break the system. Please let me know if this is suffiecient. $token = md5(rand().time()); edit: i am now using a generate_uuid() function i found on another question. will this work? function generate_uuid() { return sprintf( '%04x%04x-%04x-%04x-%04x-%04x%04x%04x', mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff ), mt_rand( 0, 0x0C2f ) | 0x4000,

问题 I'm trying to understand precisely why, when called from an external function, my time seeded random number generator returns sequences of identical numbers. Minimal working example of issue: package main import ( "fmt" "math/rand" "time" ) //Generates random int as function of range func getRand(Range int) int { s1 := rand.NewSource(time.Now().UnixNano()) r1 := rand.New(s1) return r1.Intn(Range) } //Print 100 random ints between 0 and 100 func main() { for i := 0; i < 100; i++ { fmt.Print

问题 I'm trying to understand precisely why, when called from an external function, my time seeded random number generator returns sequences of identical numbers. Minimal working example of issue: package main import ( "fmt" "math/rand" "time" ) //Generates random int as function of range func getRand(Range int) int { s1 := rand.NewSource(time.Now().UnixNano()) r1 := rand.New(s1) return r1.Intn(Range) } //Print 100 random ints between 0 and 100 func main() { for i := 0; i < 100; i++ { fmt.Print

问题 I'm new to C, I am trying to randomize 16 cards. In the longer comments I wrote something that I don't have much clear... Btw this is the code: #include <stdio.h> #include <stdlib.h> #include <time.h> #define FACES 4 #define SUITS 4 void shuffle(char *wFace[], char *wSuit[], char *wMixed[][20]); // prototype size_t checker(char *wwMixed[][20], size_t current); // prototype int main(){ char *face[] = {"Jack", "Queen", "King", "Ace"}; char *suit[] = {"Hearts", "Spades", "Diamonds", "Clubs"};

问题 I'm new to C, I am trying to randomize 16 cards. In the longer comments I wrote something that I don't have much clear... Btw this is the code: #include <stdio.h> #include <stdlib.h> #include <time.h> #define FACES 4 #define SUITS 4 void shuffle(char *wFace[], char *wSuit[], char *wMixed[][20]); // prototype size_t checker(char *wwMixed[][20], size_t current); // prototype int main(){ char *face[] = {"Jack", "Queen", "King", "Ace"}; char *suit[] = {"Hearts", "Spades", "Diamonds", "Clubs"};

问题 Generator sounds like a replacement for RandomState , and the way of the future for generating random numbers in NumPy. What features or behavior (currently or planned) does Generator have that RandomState doesn't? Both can be parameterized with BitGenerator objects. They have some different methods, but the vast majority appear to be the same. Relevant links: docs on the "legacy" RandomState Generator docs BitGenerator docs Developer's github 来源： https://stackoverflow.com/questions/61352259

问题 Generator sounds like a replacement for RandomState , and the way of the future for generating random numbers in NumPy. What features or behavior (currently or planned) does Generator have that RandomState doesn't? Both can be parameterized with BitGenerator objects. They have some different methods, but the vast majority appear to be the same. Relevant links: docs on the "legacy" RandomState Generator docs BitGenerator docs Developer's github 来源： https://stackoverflow.com/questions/61352259

问题 Generator sounds like a replacement for RandomState , and the way of the future for generating random numbers in NumPy. What features or behavior (currently or planned) does Generator have that RandomState doesn't? Both can be parameterized with BitGenerator objects. They have some different methods, but the vast majority appear to be the same. Relevant links: docs on the "legacy" RandomState Generator docs BitGenerator docs Developer's github 来源： https://stackoverflow.com/questions/61352259

问题 Consider a randomly generated __m256i vector. Is there a faster precise way to convert them into __m256 vector of floats between 0 (inclusively) and 1 (exclusively) than division by float(1ull<<32) ? Here's what I have tried so far, where iRand is the input and ans is the output: const __m256 fRand = _mm256_cvtepi32_ps(iRand); const __m256 normalized = _mm256_div_ps(fRand, _mm256_set1_ps(float(1ull<<32))); const __m256 ans = _mm256_add_ps(normalized, _mm256_set1_ps(0.5f)); 回答1: The version

问题 I want to draw a random sample from my dataset, using different proportions for each value of a factor variable, as well as using weights stored in some other column. dplyr solution in pipes will be preferred as it can be inserted easily in long code. Let's take the example of iris dataset. Species column is divided into three values 50 rows each. Let's also assume the sample weights are stored in column Sepal.Length . If I have to sample equal proportions (or equal rows) per species, the