[R] Dataframe help
iverson at biostat.wisc.edu
Wed Nov 5 17:46:38 CET 2008
> Hi there,
> I have a dataframe length.unique.info
> abc 12 345
> def 16 550
> lmn 6 600
Is this really the output when you print your data.frame? You may have
column names for columns 1, 2, and 3? Is the first column a column of
row.names, or not? What does dim(length.unique.info) give?
Assuming you have names for columns "1", "2" and "3", named, e.g., X1,
X2 and X3
subset(length.unique.info, X2 <= 5 & X3 >= 500, select = c(X1))
I don't know what you're trying to do by indexing with 'i'.
And to answer your question about '&', see ?Logic
> I want those names that fall under the condition (length.unique.info[,2][i]
> <=5 && length.unique.info[,3][i] >=500)
> abcder<-length.unique.info[which(length.unique.info[,2][i] <=5 &&
> length.unique.info[,3][i] >= 500),1]
> will "&&" look for both the condition.It isnt returning names is there
> anything i am missing.Kindly suggest me the way to do it.
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