[R] data-frame adding/deleting column

[Schmitt, Corinna]

Hallo,

I have got an existing data frame and want to add a new column. The
existing data frame was created like this:

> df <- rbind( c("Fred", "Mary", 4), c("Fred", "Mary", 7),
+                c("Fred", "Mary", 9), c("Barney", "Liz", 3),
+                c("Barney", "Liz", 5) )
> df <- data.frame(df)
> colnames(df) <- c("Father", "Mother", "Child.Age")
> df
  Father Mother Child.Age
1   Fred   Mary         4
2   Fred   Mary         7
3   Fred   Mary         9
4 Barney    Liz         3
5 Barney    Liz         5

I want to add a column named weddingdate. How does this work and how can
I save the corresponding dates in the cells? (Fred-Mary: 12.12.1980,
Barney-Liz: 3.3.2003)
How can I delet a whole column or row if it is needed?

Thanks, Corinna