如何生成介于0和n之间的随机数?
当前回答
别忘了先用srand()为RNG种子。
其他回答
也许这对你有帮助。我在应用程序中使用此功能
https://github.com/rubyworks/facets
class String
# Create a random String of given length, using given character set
#
# Character set is an Array which can contain Ranges, Arrays, Characters
#
# Examples
#
# String.random
# => "D9DxFIaqR3dr8Ct1AfmFxHxqGsmA4Oz3"
#
# String.random(10)
# => "t8BIna341S"
#
# String.random(10, ['a'..'z'])
# => "nstpvixfri"
#
# String.random(10, ['0'..'9'] )
# => "0982541042"
#
# String.random(10, ['0'..'9','A'..'F'] )
# => "3EBF48AD3D"
#
# BASE64_CHAR_SET = ["A".."Z", "a".."z", "0".."9", '_', '-']
# String.random(10, BASE64_CHAR_SET)
# => "xM_1t3qcNn"
#
# SPECIAL_CHARS = ["!", "@", "#", "$", "%", "^", "&", "*", "(", ")", "-", "_", "=", "+", "|", "/", "?", ".", ",", ";", ":", "~", "`", "[", "]", "{", "}", "<", ">"]
# BASE91_CHAR_SET = ["A".."Z", "a".."z", "0".."9", SPECIAL_CHARS]
# String.random(10, BASE91_CHAR_SET)
# => "S(Z]z,J{v;"
#
# CREDIT: Tilo Sloboda
#
# SEE: https://gist.github.com/tilo/3ee8d94871d30416feba
#
# TODO: Move to random.rb in standard library?
def self.random(len=32, character_set = ["A".."Z", "a".."z", "0".."9"])
chars = character_set.map{|x| x.is_a?(Range) ? x.to_a : x }.flatten
Array.new(len){ chars.sample }.join
end
end
https://github.com/rubyworks/facets/blob/5569b03b4c6fd25897444a266ffe25872284be2b/lib/core/facets/string/random.rb
这对我来说很好
这个呢?
n = 3
(0..n).to_a.sample
嗯,我想通了。显然有一个内置(?)函数叫做rand:
rand(n + 1)
如果有人回答了更详细的答案,我会将其标记为正确答案。
范围=10..50
兰特(范围)
or
采样范围
or
range.to_a.shuffle(这将对整个数组进行随机排序,您可以从这个数组中按第一个或最后一个或任意一个选择随机数)
尝试array#shuffle方法进行随机化
array = (1..10).to_a
array.shuffle.first
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