将行数据按因子移动到R中的列中

I have a dataset as follows:

我有如下数据集:

    > head(data)

  Symbol       Date Close
1      A 2009-01-01 15.63
2     AA 2009-01-01 11.26
3    AAP 2009-01-01 33.65
4    AAV 2009-01-01  4.21
5     AB 2009-01-01 20.79
6    ABB 2009-01-01 15.01
    >