From: nmarti <nate318i_at_yahoo.com>

Date: Thu, 24 Jul 2008 06:57:20 -0700 (PDT)

Date: Thu, 24 Jul 2008 06:57:20 -0700 (PDT)

I'm trying to calculate the percent change for a time-series variable. Basically the first several observations often look like this,

x <- c(100, 0, 0, 150, 130, 0, 0, 200, 0)

and then later in the life of the variable they're are generally no more 0's. So when I try to calculate the percent change from one observation to the next, I end up with a lot of NA/Nan/INF, and sometimes 0's which is what I want, in the beginning.

I know I can use x <- na.omit(x), and other forms of this, to get rid of some of these errors. But I would rather use some kind of function that would by defult give a 0 while dividing by zero so that I don't lose the observation, which is what happens when I use na.omit.

I would imagine this is a common problem. I tried finding something in zoo, but I haven't found what I'm looking for.

Any advice would be appreciated.

-- View this message in context: http://www.nabble.com/Dividing-by-0-tp18632469p18632469.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help_at_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.Received on Thu 24 Jul 2008 - 14:20:30 GMT

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