Dear S+ users,
I have a data frame in which the first column indicates the day number,
the second column observation number and the third results of
observations. It may look like:
Dn On R1
1 1 3
1 2 4
1 3 5
2 4 6
2 5 7
2 6 8
To find minimum value of R1 for each day is easy:
min.valR1<-Tapply(R1,Dn,min)
but how can I get not only the vector of minimum values, but also a
vector of observation numbers for which the minimum occurred I am using
S+ 4.5 for Windows.
I will appreciate any advice.
Janusz Borkowski
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