.seed()

In the Python random module, the .seed() method is used to create a pseudo-random number generator. Pseudo-random number generators appear to produce random numbers by performing some operation on a value. This value is the seed and it sets the first “random” value of the number sequence. With seeds, a user is able to reproduce the same pseudo-random numbers multiple times.

Syntax

The .seed() method sets the first random number of the generator, either with a value or without one:

random.seed(value)
random.seed()

The value can be an int, float, str, byte, bytearray, or NoneType. If one is not provied, the random number generator will use the current system time to create the seed.

Example

In most cases, the .seed() method uses the current time of the computer’s system to initialize a new generator:

import random
random.seed()
print(random.random())

Codebyte Example

In the example below, the .seed() method is used three times, once with no value and the other two with the same value of 5. In the output, each call to random.seed(5) guarantees the first pseudo-random value from the output will be the same every time:

Code
Output
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