Groups<-sample(1:9,replace = T)
SampData<-data.frame(Group=LETTERS[Groups],Value=sample(1:9,replace = T),Sample=c(1,2,3,1,1,2,2,4,3))

Group Value Sample
1     A     5      1
2     I     5      2
3     A     1      3
4     H     7      1
5     E     7      1
6     D     6      2
7     B     1      2
8     E     4      4
9     B     6      3

A  B  D  E  H  I
1  5  0  0  7  7  0
2  0  1  6  0  0  5
3  1  6  0  0  0  0
4  0  0  0  4  0  0