ruby - 如何在ruby中复制数组的值

Question

我有两个整数数组，例如

a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] 
b = [7, 8, 9]

我想重复复制 'b' 的值以获得完美匹配的数组长度，如下所示:

   a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]   
   b = [7, 8, 9, 7, 8, 9, 7, 8, 9, 7]

我们可以假设 a.length > b.length

Answer 1

假设你的意思是

a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] 
b = [7, 8, 9]

然后你可以这样做:

b.cycle.take(a.length) #=> [7, 8, 9, 7, 8, 9, 7, 8, 9, 7]

<script src="//repl.it/embed/JJ3x/2.js"></script>

参见 Array#cycle和 Enumerable#take了解更多详情。