Hi,

I have a data frame with variables a, b, c (character vars) and t (time var, 
could be represented as POSIXct or character, depending on which is most 
useful. 
The format is "yyyy-mm-dd hh:mm:ss CET"). Now, I want to sort the data frame in 
ascending order by a, b, c and then in descending order by t.

Here's what I've got, but I'm not sure how to put the 'descending' bit in the 
code. The trick with the minus sign doesn't work as the var isn't numeric. 


idvars <-- c("a", "b", "c")
myData["t"] <- as.POSIXct(myData[,"t"])
result <- myData[ do.call(order, myData[c(idvars, "t")]), ]

This should be simple, I guess, but I've been staring at this a bit too long 
now. Suggestions anyone? TIA!
Cheers!!
Albert-Jan 


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
All right, but apart from the sanitation, the medicine, education, wine, public 
order, irrigation, roads, a fresh water system, and public health, what have 
the 
Romans ever done for us?
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