[R] numbers not behaving as expected

[Uwe Ligges]

Steve_Friedman at nps.gov wrote:
> If someone can explain this odd behavior I'd appreciate it.
> 
> I have a data.frame Cell.ave (attached and created via dput(Cell.ave,
> "Cell.ave")
> which contains three columns of parameters year, month and AveRain.
> 
> I need to subset the data.frame by months such that
> 
> DrySeaonMonths are 1,2,3,4, 11, and 12 or Jan - April, November and
> December
> 
> and
> 
> WetSeasonMonths are 5:10 or May-October.
> 
> I'm using the following code:
> 
>> DrySeasonMonths <- Cell.ave[Cell.ave$month < "5" & Cell.ave$month !=
> "10",]
>> table(DrySeasonMonth$month)
>     1    2   3    4     11   12
>  36   36  36  36  36   36
> 
> #  this is expected since the data is for 36 years
> 
> WetSeasonMonths <- Cell.ave[Cell.ave$month  >= "5" & Cell.ave$month <=
> "11",]
>  WetSeasonMonths
> [1] year    month   AveRain
> <0 rows> (or 0-length row.names)
> 
> There is an obvious problem with how the values for month are being stored.
> I've tried converting them to factors, which complines that the subsetting
> routine is not appropriate for factors. And I've tried as.numeric which
> also does not return an working dataframe.
> 
> all suggestions to solve this are appreciated.
> 
> Thanks Steve
> 
> (See attached file: Cell.ave)


In fact no longer attached (removed by mailing list), but it is 
sufficient if you just tell us the result of
str(Cell.ave$month)
instead.

Uwe Ligges




> sessionInfo()
> R version 2.8.1 (2008-12-22)
> x86_64-redhat-linux-gnu
> 
> locale:
> LC_CTYPE=en_US.UTF-8;LC_NUMERIC=C;LC_TIME=en_US.UTF-8;LC_COLLATE=C;LC_MONETARY=C;LC_MESSAGES=en_US.UTF-8;LC_PAPER=en_US.UTF-8;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=en_US.UTF-8;LC_IDENTIFICATION=C
> 
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
> 
> 
> 
> Steve Friedman Ph. D.
> Spatial Statistical Analyst
> Everglades and Dry Tortugas National Park
> 950 N Krome Ave (3rd Floor)
> Homestead, Florida 33034
> 
> Steve_Friedman at nps.gov
> Office (305) 224 - 4282
> Fax     (305) 224 - 4147
> 
> 
> ------------------------------------------------------------------------
> 
> ______________________________________________
> 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.