I am trying to use the value of an ID variable in an if statement and not getting the results I expected. # ID values for two school districts> with(rf, tapply(DistrictID, DistrictName, min) )Aberdeen School Dist. # 58 Buhl Joint School District 59340 53409 This creates DNAME as I expected ... rf$DNAME[rf$DistrictID==59340] <- 'Aberdeen' rf$DNAME[rf$DistrictID==53409] <- 'Buhl'> with(rf, table(DistrictName, DNAME) )DNAME DistrictName Aberdeen Buhl Aberdeen School Dist. # 58 242 0 Buhl Joint School District 0 428 But these if statements ... if(rf$DistrictID == 59340) {rf$D.NAME <- 'Aberdeen'} if(rf$DistrictID == 53409) {rf$D.NAME <- 'Buhl'} Lead to this ... with(rf, table(DistrictName, D.NAME) ) D.NAME DistrictName Aberdeen Aberdeen School Dist. # 58 242 Buhl Joint School District 428 What am I doing wrong in the if statement? Thanks! Art ************************* Art Burke Associate, Evaluation Program Education Northwest 101 SW Main St, Ste 500 Portland, OR 97204 Phone: 503.275.9592 Art.Burke@educationnorthwest.org <mailto:Art.Burke@educationnorthwest.org> http://educationnorthwest.org <http://educationnorthwest.org/> We have recently changed our name to "Education Northwest" from "Northwest Regional Educational Laboratory." Please note the new e-mail and Web addresses in the signature above. You may continue to find us on the Web at http://www.nwrel.org <http://www.nwrel.org/> for the immediate future as well. ************************ [[alternative HTML version deleted]]
You can use the "ifelse" function for vectorized conditionals like you have here. See ?ifelse. ________________________________________ From: r-help-bounces at r-project.org [r-help-bounces at r-project.org] On Behalf Of Arthur Burke [Art.Burke at educationnorthwest.org] Sent: Tuesday, December 08, 2009 6:45 PM To: r-help at r-project.org Subject: [R] Problem with if statement I am trying to use the value of an ID variable in an if statement and not getting the results I expected. # ID values for two school districts> with(rf, tapply(DistrictID, DistrictName, min) )Aberdeen School Dist. # 58 Buhl Joint School District 59340 53409 This creates DNAME as I expected ... rf$DNAME[rf$DistrictID==59340] <- 'Aberdeen' rf$DNAME[rf$DistrictID==53409] <- 'Buhl'> with(rf, table(DistrictName, DNAME) )DNAME DistrictName Aberdeen Buhl Aberdeen School Dist. # 58 242 0 Buhl Joint School District 0 428 But these if statements ... if(rf$DistrictID == 59340) {rf$D.NAME <- 'Aberdeen'} if(rf$DistrictID == 53409) {rf$D.NAME <- 'Buhl'} Lead to this ... with(rf, table(DistrictName, D.NAME) ) D.NAME DistrictName Aberdeen Aberdeen School Dist. # 58 242 Buhl Joint School District 428 What am I doing wrong in the if statement? Thanks! Art ************************* Art Burke Associate, Evaluation Program Education Northwest 101 SW Main St, Ste 500 Portland, OR 97204 Phone: 503.275.9592 Art.Burke at educationnorthwest.org <mailto:Art.Burke at educationnorthwest.org> http://educationnorthwest.org <http://educationnorthwest.org/> We have recently changed our name to "Education Northwest" from "Northwest Regional Educational Laboratory." Please note the new e-mail and Web addresses in the signature above. You may continue to find us on the Web at http://www.nwrel.org <http://www.nwrel.org/> for the immediate future as well. ************************ [[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.
It would be easier to answer if a portion of the input were shown in
the question using dput(rf) or dput(head(rf)) but lets assume it looks
like this and that our objective is to display a table of Name vs.
DNAME counts where DNAME consists of manufactured short names -- is
that right?
DF <- data.frame(ID = c(10, 20, 10), Name = c("A blah", "B
blah", "A blah"))
# Then here are several alternatives:
# 1. using assignment as in original question
DF1 <- DF
DF1$DNAME[DF1$ID == 10] <- "A"
DF1$DNAME[DF1$ID == 20] <- "B"
with(DF1, table(Name, DNAME))
# 2. using ifelse
DF2 <- DF
DF$NAME <- ifelse(DF2$ID == 10, "A", "B")
# 3. using sub assuming first word is unique
DF3 <- transform(DF, DNAME = sub(" .*", "", Name))
with(DF3, table(Name, DNAME))
# 4. using abbreviate although abbreviated names do not always look nice
DF4 <- transform(DF, DNAME = abbreviate(Name))
with(DF4, table(Name, DNAME))
# 5. subscripting by name
shortNames <- c("A blah" = "A", "B blah" =
"B")
DF5 <- transform(DF, DNAME = shortNames[Name])
with(DF5, table(Name, DNAME))
On Tue, Dec 8, 2009 at 7:45 PM, Arthur Burke
<Art.Burke at educationnorthwest.org> wrote:> I am trying to use the value of an ID variable in an if statement and
> not getting the results I expected.
>
> # ID values for two school districts
>> with(rf, tapply(DistrictID, DistrictName, min) )
>
> Aberdeen School Dist. # 58 ? ? ? ? Buhl Joint School District
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? 59340 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?53409
>
>
> This creates DNAME as I expected ...
>
> rf$DNAME[rf$DistrictID==59340] <- 'Aberdeen'
> rf$DNAME[rf$DistrictID==53409] <- 'Buhl'
>
>
>> with(rf, table(DistrictName, DNAME) )
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?DNAME
> DistrictName ? ? ? ? ? ? ? ? ? ? ? ? Aberdeen Buhl
> ?Aberdeen School Dist. # 58 ? ? ? ? ? ? ?242 ? ?0
> ?Buhl Joint School District ? ? ? ? ? ? ? ?0 ?428
>
> But these if statements ...
>
> if(rf$DistrictID == 59340) {rf$D.NAME <- 'Aberdeen'}
> if(rf$DistrictID == 53409) {rf$D.NAME <- 'Buhl'}
>
>
> Lead to this ...
>
> with(rf, table(DistrictName, D.NAME) )
>
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?D.NAME
> DistrictName ? ? ? ? ? ? ? ? ? ? ? ? Aberdeen
> ?Aberdeen School Dist. # 58 ? ? ? ? ? ? ?242
> ?Buhl Joint School District ? ? ? ? ? ? ?428
>
>
> What am I doing wrong in the if statement?
>
> Thanks!
> Art
>
> *************************
>
> Art Burke
>
> Associate, Evaluation Program
>
> Education Northwest
>
> 101 SW Main St, Ste 500
>
> Portland, OR 97204
>
> Phone: 503.275.9592
>
> Art.Burke at educationnorthwest.org
> <mailto:Art.Burke at educationnorthwest.org>
>
> http://educationnorthwest.org <http://educationnorthwest.org/>
>
> We have recently changed our name to "Education Northwest" from
> "Northwest Regional Educational Laboratory." Please note the new
e-mail
> and Web addresses in the signature above. You may continue to find us on
> the Web at http://www.nwrel.org <http://www.nwrel.org/> ?for the
> immediate future as well.
>
> ************************
>
>
> ? ? ? ?[[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.
>