[R] Designating a new year (Sept-Aug) in R

[arun]

Hi,
Try this:
dat1<-read.table(text="
site,date,precipitation,temp_max,temp_min
Castle Peak,January-70,0,32,18
Castle Peak,January-70,0,39,9
Castle Peak,September-70,0,34,5
Castle Peak,September-70,0,30,7
Castle Peak,October-70,0,40,6
Castle Peak,November-70,0,45,10
Castle Peak,December-70,0,43,8
Castle Peak,October-71,0,42,7
Castle Peak,November-71,0,46,11
Castle Peak,December-71,0,41,9
",sep=",",stringsAsFactors=FALSE,header=TRUE)

Month1<-c("September","October","November","December")

 dat1$date[gsub("(.*)\\-.*","\\1",dat1$date)%in%Month1]<-paste0(gsub("(.*\\-).*","\\1",dat1$date[gsub("(.*)\\-.*","\\1",dat1$date)%in%Month1]),as.numeric(gsub(".*\\-(.*)","\\1",dat1$date[gsub("(.*)\\-.*","\\1",dat1$date)%in%Month1]))+1)
dat1
#          site         date precipitation temp_max temp_min
#1  Castle Peak   January-70             0       32       18
#2  Castle Peak   January-70             0       39        9
#3  Castle Peak September-71             0       34        5
#4  Castle Peak September-71             0       30        7
#5  Castle Peak   October-71             0       40        6
#6  Castle Peak  November-71             0       45       10
#7  Castle Peak  December-71             0       43        8
#8  Castle Peak   October-72             0       42        7
#9  Castle Peak  November-72             0       46       11
#10 Castle Peak  December-72             0       41        9
A.K.

A.K.




----- Original Message -----
From: nick pardikes <npardikes at hotmail.com>
To: "r-help at R-project.org" <r-help at r-project.org>
Cc: 
Sent: Saturday, November 24, 2012 4:01 PM
Subject: [R] Designating a new year (Sept-Aug) in R

If I have data (below) and need some help in figuring out how I can change the values of my date column, so that a year will be from September-August? So the year 
1990 = September 89-August 90; 1991
= September 90-August 91, etc... 

I was trying to use the if() function, but am unable to figure it out. I basically need to change the years associated with September-December to the following year. Any 
help would be greatly appreciated. Otherwise I will have to power through
it and do it all manually in excel. I am sorry that I do not have the original data associated with this posting, nor any R code with it. I really do not have a clue how to even start designating the new year. 

head(mydata)
class(mydata)
"data.frame"
         site            date                precipitation temp_max temp_min
1 Castle Peak January-70             0       32       18
2 Castle Peak January-70             0       39        9
3 Castle Peak January-70             0       34        5
4 Castle Peak January-70             0       30        7
5 Castle Peak January-70             0       40        6
6 Castle Peak January-70             0       45       10

Thank you in advance and please let me know what else I can include to help solve this issue. this is my first posting on R-help. 



Nick Pardikes
PhD Student
Program in Ecology, Evolution and Conservation Biology
University of Nevada, Reno
303-550-1072
http://wolfweb.unr.edu/homepage/npardikes/MySite/Welcome.html
                          
    [[alternative HTML version deleted]]

______________________________________________
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.