AnsWiki | In C, what is the purpose of the srand() function?

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In C, what is the purpose of the srand() function?

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The ﻿srand() function is used to initialize the pseudo-random generator, because the ﻿rand() function does not really draw numbers at random Computers are unable to produce real random numbers, they classically use pseudo-random generators that actually generate sequences of numbers that have properties similar to random numbers The problem is that, with identical initial conditions, the generated sequences are always identical  To obtain different sequences of numbers, which is generally the case when using a pseudo-random generator, it is necessary to initialize the sequence in a different way  This is called the seed  The function ﻿srand (unsigned int seed) allows to initialize the pseudo-random generator The solution commonly adopted to initialize the generator is to use the current time of the machine which, as it is constantly changing, will produce seeds and therefore numbers which will be different at each moment  Hence the execution of the following code:// initialize the pseudo-random generator  rand (time(NULL))See also :How to draw a random number in C?In C, how do you pick a random number in an interval?In which library is the rand() function in C ?

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The ﻿srand() function is used to initialize the pseudo-random generator, because the ﻿rand() function does not really draw numbers at random Computers are unable to produce real random numbers, they classically use pseudo-random generators that actually generate sequences of numbers that have properties similar to random numbers The problem is that, with identical initial conditions, the generated sequences are always identical  To obtain different sequences of numbers, which is generally the case when using a pseudo-random generator, it is necessary to initialize the sequence in a different way  This is called the seed  The function ﻿srand (unsigned int seed) allows to initialize the pseudo-random generator The solution commonly adopted to initialize the generator is to use the current time of the machine which, as it is constantly changing, will produce seeds and therefore numbers which will be different at each moment  Hence the execution of the following code:// initialize the pseudo-random generator  rand (time(NULL))See also :How to draw a random number in C?In which library is the rand() function in C ?

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The ﻿srand() function is used to initialize the pseudo-random generator, because the ﻿rand() function does not really draw numbers at random Computers are unable to produce real random numbers, they classically use pseudo-random generators that actually generate sequences of numbers that have properties similar to random numbers The problem is that, with identical initial conditions, the generated sequences are always identical  To obtain different sequences of numbers, which is generally the case when using a pseudo-random generator, it is necessary to initialize the sequence in a different way  This is called the seed  The function ﻿srand (unsigned int seed) allows to initialize the pseudo-random generator The solution commonly adopted to initialize the generator is to use the current time of the machine which, as it is constantly changing, will produce seeds and therefore numbers which will be different at each moment  Hence the execution of the following code:// initialize the pseudo-random generator  rand (time(NULL))See also :How to draw a random number in C?In which library is the rand() function in C ?

Answiki · Answer

The ﻿srand() function is used to initialize the pseudo-random generator, because the ﻿rand() function does not really draw numbers at random Computers are unable to produce real random numbers, they classically use pseudo-random generators that actually generate sequences of numbers that have properties similar to random numbers The problem is that, with identical initial conditions, the generated sequences are always identical  To obtain different sequences of numbers, which is generally the case when using a pseudo-random generator, it is necessary to initialize the sequence in a different way  This is called the seed  The function ﻿srand (unsigned int seed) allows to initialize the pseudo-random generator The solution commonly adopted to initialize the generator is to use the current time of the machine which, as it is constantly changing, will produce seeds and therefore numbers which will be different at each moment  Hence the execution of the following code:// initialize the pseudo-random generator  rand (time(NULL))See also :How to draw a random number in C?In which library is the rand() function in C ?

Answiki · Answer

The ﻿srand() function is used to initialize the pseudo-random generator, because the ﻿rand() function does not really draw numbers at random Computers are unable to produce real random numbers, they classically use pseudo-random generators that actually generate sequences of numbers that have properties similar to random numbers The problem is that, with identical initial conditions, the generated sequences are always identical  To obtain different sequences of numbers, which is generally the case when using a pseudo-random generator, it is necessary to initialize the sequence in a different way  This is called the seed  The function ﻿srand (unsigned int seed) allows to initialize the pseudo-random generator The solution commonly adopted to initialize the generator is to use the current time of the machine which, as it is constantly changing, will produce seeds and therefore numbers which will be different at each moment  Hence the execution of the following code:// initialize the pseudo-random generator  rand (time(NULL))See also :How to draw a random number in C?In which library is the rand() function in C ?

Answiki · Answer

The ﻿srand() function is used to initialize the pseudo-random generator, because the ﻿rand() function does not really draw numbers at random Computers are unable to produce real random numbers, they classically use pseudo-random generators that actually generate sequences of numbers that have properties similar to random numbers The problem is that, with identical initial conditions, the generated sequences are always identical  To obtain different sequences of numbers, which is generally the case when using a pseudo-random generator, it is necessary to initialize the sequence in a different way  This is called the seed  The function ﻿srand (unsigned int seed) allows to initialize the pseudo-random generator The solution commonly adopted to initialize the generator is to use the current time of the machine which, as it is constantly changing, will produce seeds and therefore numbers which will be different at each moment  Hence the execution of the following code:// initialize the pseudo-random generator  rand (time(NULL))Voire aussi :Comment tirer un nombre aléatoire en C ?Dans quelle bibliothèque se trouve la fonction rand() en C ?