Maybe we need to backtrack a bit. You originally were complaining
about an error that said you had duplicated index entries as you
attempted to make a zoo object. I assumed, incorrectly it now
appears, that you understood that an index in a zoo object was a
vector. You now seem to be admitting that you were trying to use an
entire dataframe as your index. As the acronym goes, ... DDT.
On Jan 3, 2012, at 1:53 PM, Rich Shepard wrote:
On Tue, 3 Jan 2012, David Winsemius wrote:
That's rather unconvincing. What does this show:
burns.tds[ !duplicated(burns.tds) ]
I saw that in the help page but assumed it was the opposite of
duplicated;
apparently not.
burns.tds[ !duplicated(burns.tds) ]
Error in .data.frame(burns.tds, !duplicated(burns.tds)) :
undefined columns selected
Right. If you had said it was a dataframe, I would have suggested:
burns.tds[ !duplicated(burns.tds) , ]
But that would only identify entire duplicated rows; it would not
cure the misguided notion of creating a zoo-index from a dataframe.
burns.tds was generated by
burns.tds <- subset(chemdata, stream == 'BurnsCrk', select = c(site,
sampdate, param == 'TDS', quant), drop = T)
and has this structure
'data.frame': 2472 obs. of 3 variables:
$ site : Factor w/ 137 levels "BC-0.5","BC-1",..: 5 5 5 5 5 5 5
5 ...
$ sampdate: Factor w/ 1056 levels "1978-03-28","1978-04-11",..: 155
156 158
161 163 164 172 175 177 309 ...
$ quant : num 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 8.08 ...
Because the data frame chemdata came from a relational table with a
primary key of (site, sampdate, param) I am having trouble
understanding
where duplicate rows could have originated.
You still have not really described what your are trying to do ... or
with what data you are trying to do it with. You might want to think
about taking that sampdate which is now a factor and turinging it into
a data object which would then satisfy the requirements of an index
for a zoo object. The second letter in "zoo" stands for "ordered" and
factors have no order.
--
David Winsemius, MD
West Hartford, CT
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
