How to generate random numbers in Python?

Question

I would like to know how to generate random numbers in Python. I’m with version 3.4.

Answer 1

from random import randint
print(randint(0,9))

This generates integer numbers between 0 and 9.

It is possible to use several other functions available in documentation. Each one can be better for what you want.

from random import randrange, uniform
print(randrange(0, 9)) #faixa de inteiro
print(uniform(0, 9)) #faixa de ponto flutuante

You can import everything and use what you want:

from random import *
random.seed() #inicia a semente dos número pseudo randômicos
random.randrange(0, 9, 2) # pares entre 0 e 9
random.choice('abcdefghij') # seleciona um dos elementos aleatoriamente
items = [1, 2, 3, 4, 5, 6, 7]
random.shuffle(items) # embaralha os itens aleatoriamente

I put in the Github for future reference.

Answer 2

from random import *
print random()
print uniform(10,20)
print randint(100,1000)
print randrange(100,1000,2)

random() returns a float x such that 0 <= x < 1.

uniform(10,20) returns a float x such that 10 <= x < 20.

randint(100,1000) returns a inteiro x such that 100 <= x < 1000.

randrange(100,1000,2) returns a inteiro x such that 100 <= x < 1000 and x is even

Answer 3

I can’t comment yet because I don’t have a score for it, but randint includes the last paragraph, as opposed to randrange, which works more like the rest of Python (closed interval at the beginning and open at the end). So, in the lai0n response, randint(100,1000) includes the 1000 in the possibilities. At least in Python 3.4, which is what I use. Logo, randrange(a, b+1) is the same as randint(a, b)

Answer 4

Use the Random method combined with some class of it. ex:

import random

num = int(input('O computador pensou em um numero entre 0 e 5, você é capaz de advinhar? '))
sorteio = random.randint(0, 5)

if num == sorteio:
    print('Parabens, o numero pensando pelo computador foi {}, o mesmo do seu!!!'.format(sorteio))
else:
    print('Que pena, você nao acertou!!')

Answer 5

I leave here a suggestion function, which generates random numbers (from 0.0 to 1.0) in a vector with a given size:

def gerar():
   from random import random
   tamanho = int(input())
   resposta = [0.0] * tamanho
   for i in range(tamanho):
       resposta[i] = random()
   return resposta