怎样随机从数组选？ [英] How do I pick randomly from an array?

问题描述

我想知道是否有这样做的更清洁的方式。基本上，我想从可变长度的数组选择一个随机元素。通常情况下，我会做这样的：

I want to know if there is a much cleaner way of doing this. Basically, I want to pick a random element from an array of variable length. Normally, I would do it like this:

myArray = ["stuff", "widget", "ruby", "goodies", "java", "emerald", "etc" ]
item = myArray[rand(myarray.length)]

有什么是更可读/可简单更换第二行？或者是，最好的方式做到这一点。我想你可以做 myArray.shuffle.first ，但我只看到了 #shuffle 几分钟前的SO，我还没有实际使用它。

Is there something that is more readable / simpler to replace the second line? Or is that the best way to do it. I suppose you could do myArray.shuffle.first, but I only saw #shuffle a few minutes ago on SO, I haven't actually used it yet.

推荐答案

只需使用的 阵列＃示例 ：

Just use Array#sample:

[:foo, :bar].sample # => :foo, or :bar :-)

这是用Ruby 1.9.1+可用。为了还能够使用Ruby的早期版本使用它，你可以 规定反向移植/ 1.9.1 /阵列/样本 。

请注意在Ruby中1.8.7存在下，不幸的名称选;它是在新版本改名所以你不应该使用的。

Note that in Ruby 1.8.7 it exists under the unfortunate name choice; it was renamed in later version so you shouldn't use that.

虽然在这种情况下没有用的，样品接受的情况下，你要多个不同样本的数字参数。

Although not useful in this case, sample accepts a number argument in case you want a number of distinct samples.

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