Scriptling Scriptling

random

The random library generates random integers, floats, and samples, including several statistical distributions, with an API that follows Python’s random module.

Available Functions

Function Description
seed([a]) Initialize the random number generator.
randint(a, b) Random integer between a and b (inclusive).
randrange(start, stop[, step]) Random integer from a range.
random() Random float in [0.0, 1.0).
uniform(a, b) Random float between a and b.
choice(seq) Random element from a sequence.
shuffle(x) Shuffle a list in place.
sample(population, k) k unique random elements from a list or set (without replacement).
choices(population, weights=None, k=1) k elements with replacement, optionally weighted (weights and k may be positional or keyword).
gauss(mu, sigma) Random float from a Gaussian distribution.
normalvariate(mu, sigma) Alias for gauss().
expovariate(lambd) Random float from an exponential distribution (lambd is 1 / mean).
betavariate(alpha, beta) Random float from a beta distribution.
gammavariate(alpha, beta) Random float from a gamma distribution.
triangular(low, high[, mode]) Random float from a triangular distribution.
paretovariate(alpha) Random float from a Pareto distribution.
weibullvariate(alpha, beta) Random float from a Weibull distribution.

Example

import random

random.seed(42)                       # reproducible sequence (values differ from CPython's)

roll = random.randint(1, 6)           # 1..6 inclusive
step = random.randrange(0, 100, 5)    # 0, 5, ..., 95
p = random.random()                   # 0.0 <= p < 1.0
t = random.uniform(20.0, 30.0)        # float between the bounds
print(1 <= roll <= 6, step % 5 == 0, 0 <= p < 1, 20 <= t <= 30)  # True True True True

colors = ["red", "green", "blue"]
print(random.choice(colors) in colors)                 # True
print(len(random.choices(colors, weights=[5, 3, 2], k=10)))  # 10 (with replacement)
lottery = random.sample(list(range(1, 50)), 6)         # 6 unique values
print(len(set(lottery)))                               # 6

deck = list(range(1, 53))
random.shuffle(deck)                                   # in place, returns None
print(sorted(deck) == list(range(1, 53)))              # True

noise = random.gauss(0, 1)            # also normalvariate, expovariate(1/mean),
wait = random.expovariate(0.2)        # betavariate, gammavariate, triangular,
peak = random.triangular(0, 10, 7)    # paretovariate, weibullvariate

Differences from Python

  • Seeded sequences are reproducible within Scriptling but do not match CPython’s values for the same seed.
  • shuffle() accepts only a list.
  • There is no random.Random class, and getrandbits, randbytes, getstate/setstate, lognormvariate, vonmisesvariate and binomialvariate are not available. For security-sensitive values use secrets.

See Also

  • math: mathematical functions and constants.
  • statistics: mean, median, variance, and other statistical functions.
  • uuid: UUID generation.