Dear helpeRs, I have a dataframe (14947 x 27) containing measurements collected every 5 seconds at several different sampling locations. If one measurement at a given location is less than zero on a given day, I would like to delete all measurements from that location on that day. Here is a toy example: toy <- data.frame(CH = rep(3:5,3), DAY = c(rep(4,5), rep(5,4)), SLOPE = c(seq(0.2,0.6, .1),seq(0.2, -0.1, -0.1))) In this example, row 9 has a negative measurement for Chamber 5, so I would like to delete row 6, which is the same Chamber on the same day, but not row 3, which is the same chamber on a different day. In the full dataframe, there are, of course, many more days. Is there a handy R way to do this? Thank you for the assistance. Toby
Try this:
subset(toy, !rowSums(mapply(is.element, toy[c('CH', 'DAY')],
subset(toy,
SLOPE < 0, CH:DAY))) > 1 | SLOPE < 0)
On Thu, Aug 12, 2010 at 4:11 PM, Toby Gass
<tobygass@warnercnr.colostate.edu> wrote:
> Dear helpeRs,
>
> I have a dataframe (14947 x 27) containing measurements collected
> every 5 seconds at several different sampling locations. If one
> measurement at a given location is less than zero on a given day, I
> would like to delete all measurements from that location on that day.
>
> Here is a toy example:
>
> toy <- data.frame(CH = rep(3:5,3), DAY = c(rep(4,5), rep(5,4)),
> SLOPE = c(seq(0.2,0.6, .1),seq(0.2, -0.1, -0.1)))
>
> In this example, row 9 has a negative measurement for Chamber 5, so I
> would like to delete row 6, which is the same Chamber on the same
> day, but not row 3, which is the same chamber on a different day. In
> the full dataframe, there are, of course, many more days.
>
> Is there a handy R way to do this?
>
> Thank you for the assistance.
>
> Toby
>
> ______________________________________________
> 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.
>
--
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40" S 49° 16' 22" O
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On Aug 12, 2010, at 3:11 PM, Toby Gass wrote:> Dear helpeRs, > > I have a dataframe (14947 x 27) containing measurements collected > every 5 seconds at several different sampling locations. If one > measurement at a given location is less than zero on a given day, I > would like to delete all measurements from that location on that day. > > Here is a toy example: > > toy <- data.frame(CH = rep(3:5,3), DAY = c(rep(4,5), rep(5,4)), > SLOPE = c(seq(0.2,0.6, .1),seq(0.2, -0.1, -0.1))) > > In this example, row 9 has a negative measurement for Chamber 5, so I > would like to delete row 6, which is the same Chamber on the same > day, but not row 3, which is the same chamber on a different day. In > the full dataframe, there are, of course, many more days. > > Is there a handy R way to do this?toy[ - which(toy$SLOPE <0 ) , ]> > Thank you for the assistance. > > Toby > > ______________________________________________ > 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.David Winsemius, MD West Hartford, CT
On Aug 12, 2010, at 2:11 PM, Toby Gass wrote:> Dear helpeRs, > > I have a dataframe (14947 x 27) containing measurements collected > every 5 seconds at several different sampling locations. If one > measurement at a given location is less than zero on a given day, I > would like to delete all measurements from that location on that day. > > Here is a toy example: > > toy <- data.frame(CH = rep(3:5,3), DAY = c(rep(4,5), rep(5,4)), > SLOPE = c(seq(0.2,0.6, .1),seq(0.2, -0.1, -0.1))) > > In this example, row 9 has a negative measurement for Chamber 5, so I > would like to delete row 6, which is the same Chamber on the same > day, but not row 3, which is the same chamber on a different day. In > the full dataframe, there are, of course, many more days. > > Is there a handy R way to do this? > > Thank you for the assistance. > > TobyNot fully tested, but here is one possibility:> toyCH DAY SLOPE 1 3 4 0.2 2 4 4 0.3 3 5 4 0.4 4 3 4 0.5 5 4 4 0.6 6 5 5 0.2 7 3 5 0.1 8 4 5 0.0 9 5 5 -0.1> subset(toy, ave(SLOPE, CH, DAY, FUN = function(x) any(x < 0)) == 0)CH DAY SLOPE 1 3 4 0.2 2 4 4 0.3 3 5 4 0.4 4 3 4 0.5 5 4 4 0.6 7 3 5 0.1 8 4 5 0.0 See ?ave and ?subset HTH, Marc Schwartz
On Aug 12, 2010, at 2:24 PM, Marc Schwartz wrote:> On Aug 12, 2010, at 2:11 PM, Toby Gass wrote: > >> Dear helpeRs, >> >> I have a dataframe (14947 x 27) containing measurements collected >> every 5 seconds at several different sampling locations. If one >> measurement at a given location is less than zero on a given day, I >> would like to delete all measurements from that location on that day. >> >> Here is a toy example: >> >> toy <- data.frame(CH = rep(3:5,3), DAY = c(rep(4,5), rep(5,4)), >> SLOPE = c(seq(0.2,0.6, .1),seq(0.2, -0.1, -0.1))) >> >> In this example, row 9 has a negative measurement for Chamber 5, so I >> would like to delete row 6, which is the same Chamber on the same >> day, but not row 3, which is the same chamber on a different day. In >> the full dataframe, there are, of course, many more days. >> >> Is there a handy R way to do this? >> >> Thank you for the assistance. >> >> Toby > > > > Not fully tested, but here is one possibility: > >> toy > CH DAY SLOPE > 1 3 4 0.2 > 2 4 4 0.3 > 3 5 4 0.4 > 4 3 4 0.5 > 5 4 4 0.6 > 6 5 5 0.2 > 7 3 5 0.1 > 8 4 5 0.0 > 9 5 5 -0.1 > > >> subset(toy, ave(SLOPE, CH, DAY, FUN = function(x) any(x < 0)) == 0) > CH DAY SLOPE > 1 3 4 0.2 > 2 4 4 0.3 > 3 5 4 0.4 > 4 3 4 0.5 > 5 4 4 0.6 > 7 3 5 0.1 > 8 4 5 0.0This can actually be slightly shortened to:> subset(toy, !ave(SLOPE, CH, DAY, FUN = function(x) any(x < 0)))CH DAY SLOPE 1 3 4 0.2 2 4 4 0.3 3 5 4 0.4 4 3 4 0.5 5 4 4 0.6 7 3 5 0.1 8 4 5 0.0 HTH, Marc