[R] cumulative frequency plots for factors

[Dieter Vanderelst]

Dear list,

I have a data frame with a number of events (factor) and the times at which they occurred (continuous variable):

event time
A 10
A 12
B 15
A 17
C 13
...

Is it possible in R to make a plot against time of the cumulative frequency of occurrence of each event? This would be, a raising line for each factor.

Regards,
Dieter