Hello,
I've not been following this thread but this seems ndependent from
previous posts. Try the following.
url <- "http://r.789695.n4.nabble.com/file/n4636337/BR3_2011_New.csv";
tUnitsort <- read.csv(url, header=TRUE)
cols <- sapply(c("Date", "Hour", "BlockNumber", "MyTo"), function(x)
grep(x, names(tUnitsort)))
# This does it
# Use full data.frame 'tUnitsort' if you want
data.tmp <- aggregate(MyTo ~ Date + Hour, data = tUnitsort[, cols], max)
data.tmp <- merge(tUnitsort[, cols], data.tmp, by=c("Date", "Hour"))
# Make it pretty
idx <- grep("MyTo", names(data.tmp))
names(data.tmp)[idx] <- c("MyTo", "NewColumn")
# See it
head(data.tmp, 20)
tail(data.tmp, 20)
Also, you should quote the context. Many, almost all of us do NOT read
the posts on Nabble. And Nabble does have a "quote" button.
Hope this helps,
Rui Barradas
Em 12-07-2012 18:55, jcrosbie escreveu:
Thank you,
I am sorry but I am still trying to figure out how to make the function
work.
I have a column called tUnitsort$BlockNumber which can range from 0 to 6.
I have another two columns with the date and the hour ending for the given
day.
Example
Date Hour BlockNumber MyTo NewColumn
2011-01 1 2 140 140
2011-01 1 1 70 140
2011-01 1 0 0 140
2011-02 1 2 160 160
2011-02 1 1 70 160
2011-02 1 0 0 160
2011-03 1 2 150 150
I want to create a NewColumn which will place the MyTo number for the
highest block number for the rest blocks in a given hour ending within a
day.
ifelse(tUnitsort[,4]>=tUnitsort[-1,4],tUnitsort[,7],tUnitsort[-1,7])
I am unsure how to refference the element before in this case. I thought
the -1 was doing this but I believe I'm wrong now.
http://r.789695.n4.nabble.com/file/n4636337/BR3_2011_New.csv
BR3_2011_New.csv
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