Help with cast/reshape

I realize that this is terribly basic, but I just don't seem to see it 

this moment, so I would very much appreciate your help.


How shall I transform this dataframe:

df1

  Name Index Value
1    a     1   0.1
2    a     2   0.2
3    a     3   0.3
4    a     4   0.4
5    b     1   2.1
6    b     2   2.2
7    b     3   2.3
8    b     4   2.4


into this dataframe:

df2

    Index  a       b
1  1     0.1     2.1
2  2     0.2     2.2
3  3     0.3     2.3
4  4     0.4     2.4

df1 = data.frame(c("a", "a", "a", "a", "b", "b", "b", "b"), 

3,4), c(0.1, 0.2, 0.3, 0.4, 2.1, 2.2, 2.3, 2.4))
colnames(df1) = c("Name", "Index", "Value")

df2 = data.frame(c(1,2,3,4), c(0.1, 0.2, 0.3, 0.4), c(2.1, 2.2, 2.3, 

colnames(df2) = c("Index", "a", "b")


Thank you very much.

Dana