Re: [R] Sum function and missing values --- need to mimic SAS sum function
On 01/27/2015 02:54 AM, Bert Gunter wrote:
Huh??
ifelse(TRUE, a <- 2L, a <- 3L)
[1] 2
a
[1] 2
Please clarify.
In Bioconductor ifelse() is a generic function (with methods for Rle
objects) so all its arguments are evaluated before dispatch can
happen. You can reproduce with:
setGeneric("ifelse")
## A dummy method so the dispatch mechanism will need to evaluate th
## 'no' arg before dispatch can actually happen.
setMethod("ifelse", c(no="data.frame"),
function(test, yes, no)
stop("I'm kind of broken on data frames, don't use me like that"))
Then:
> ifelse(TRUE, a <- 2L, a <- 3L)
[1] 2
> a
[1] 3
Delay evaluation is a world full of surprises...
H.
-- Bert
Bert Gunter
Genentech Nonclinical Biostatistics
(650) 467-7374
"Data is not information. Information is not knowledge. And knowledge
is certainly not wisdom."
Clifford Stoll
On Mon, Jan 26, 2015 at 2:22 PM, Hervé Pagès wrote:
Hi Martin,
On 01/26/2015 04:45 AM, Martin Maechler wrote:
Jim Lemon
on Mon, 26 Jan 2015 11:21:03 +1100 writes:
> Hi Allen, How about this:
> sum_w_NA<-function(x) ifelse(all(is.na(x)),NA,sum(x,na.rm=TRUE))
Excuse, Jim, but that's yet another "horrible misuse of ifelse()"
John Fox's reply *did* contain the "proper" solution
if (all(is.na(x))) NA else sum(x, na.rm=TRUE)
The ifelse() function should never be used in such cases.
Read more after googling
"Do NOT use ifelse()"
-- include the quotes in your search --
or directly at
http://stat.ethz.ch/pipermail/r-help/2014-December/424367.html
Interesting. You could have added the following item to your list:
4. less likely to play strange tricks on you:
> ifelse(TRUE, a <- 2L, a <- 3L)
[1] 2
> a
[1] 3
Yeah I've seen people using ifelse() that way and being totally
confused...
Cheers,
H.
Yes, this has been on R-help a month ago..
Martin
> On Mon, Jan 26, 2015 at 10:21 AM, Allen Bingham
> wrote:
>> I understand that in order to get the sum function to
>> ignore missing values I need to supply the argument
>> na.rm=TRUE. However, when summing numeric values in which
>> ALL components are "NA" ... the result is 0.0 ... instead
>> of (what I would get from SAS) of NA (or in the case of
>> SAS ".").
>>
>> Accordingly, I've had to go to 'extreme' measures to get
>> the sum function to result in NA if all arguments are
>> missing (otherwise give me a sum of all non-NA elements).
>>
>> So for example here's a snippet of code that ALMOST does
>> what I want:
>>
>>
>>
SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2),
>> select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE)
>>
>> In reality this does NOT give me records with NA for
>> SumValue ... but it doesn't give me values for any
>> records in which both Variable.1 and Variable.2 are NA
>> --- which is "good enough" for my purposes.
>>
>> I'm guessing with a little more work I could come up with
>> a way to adapt the code above so that I could get it to
>> work like SAS's sum function ...
>>
>> ... but before I go that extra mile I thought I'd ask
>> others if they know of functions in either base R ... or
>> in a package that will better mimic the SAS sum function.
>>
>> Any suggestions?
>>
>> Thanks. __ Allen
>> Bingham aebingh...@gmail.com
>>
>> __
>> R-help@r-project.org mailing list -- To UNSUBSCRIBE and
>> more, see 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.
> __
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and
> more, see 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.
__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.
--
Hervé Pagès
Program in Computational Biology
Division of Public Health Sciences
Fred Hutchinson Cancer Research Center
1100 Fairview Ave. N, M1-B514
P.O. Box 19024
Seattle, WA 98109-1024
E-mail: hpa...@fredhutch.org
Phone: (206) 667-5791
Fax:(206) 667-1319
__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz
Re: [R] Sum function and missing values --- need to mimic SAS sum function
Hi, Not sure if the following is what you look for: >x <- c(1:10, NA, 12:20) >sum(x[!is.na(x)]) -- View this message in context: http://r.789695.n4.nabble.com/Sum-function-and-missing-values-need-to-mimic-SAS-sum-function-tp4702344p4702392.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
Maybe this is due to the usage of rep() in ifelse():
f.rep <- function(ans){ans <- rep(ans,1);return(ans)}
f <- function(ans){return(ans)}
f(a <- 123) # no print here
f.rep(a <- 123) # prints:
# [1] 123
On 27 January 2015 at 11:54, Bert Gunter wrote:
> Huh??
>
>> ifelse(TRUE, a <- 2L, a <- 3L)
> [1] 2
>> a
> [1] 2
>
> Please clarify.
>
> -- Bert
>
> Bert Gunter
> Genentech Nonclinical Biostatistics
> (650) 467-7374
>
> "Data is not information. Information is not knowledge. And knowledge
> is certainly not wisdom."
> Clifford Stoll
>
>
>
>
> On Mon, Jan 26, 2015 at 2:22 PM, Hervé Pagès wrote:
>> Hi Martin,
>>
>> On 01/26/2015 04:45 AM, Martin Maechler wrote:
Jim Lemon
on Mon, 26 Jan 2015 11:21:03 +1100 writes:
>>>
>>>
>>> > Hi Allen, How about this:
>>>
>>> > sum_w_NA<-function(x) ifelse(all(is.na(x)),NA,sum(x,na.rm=TRUE))
>>>
>>> Excuse, Jim, but that's yet another "horrible misuse of ifelse()"
>>>
>>> John Fox's reply *did* contain the "proper" solution
>>>
>>> if (all(is.na(x))) NA else sum(x, na.rm=TRUE)
>>>
>>> The ifelse() function should never be used in such cases.
>>> Read more after googling
>>>
>>> "Do NOT use ifelse()"
>>>
>>> -- include the quotes in your search --
>>>
>>> or directly at
>>> http://stat.ethz.ch/pipermail/r-help/2014-December/424367.html
>>
>>
>> Interesting. You could have added the following item to your list:
>>
>> 4. less likely to play strange tricks on you:
>>
>> > ifelse(TRUE, a <- 2L, a <- 3L)
>> [1] 2
>> > a
>> [1] 3
>>
>> Yeah I've seen people using ifelse() that way and being totally
>> confused...
>>
>> Cheers,
>> H.
>>
>>>
>>> Yes, this has been on R-help a month ago..
>>> Martin
>>>
>>> > On Mon, Jan 26, 2015 at 10:21 AM, Allen Bingham
>>> > wrote:
>>> >> I understand that in order to get the sum function to
>>> >> ignore missing values I need to supply the argument
>>> >> na.rm=TRUE. However, when summing numeric values in which
>>> >> ALL components are "NA" ... the result is 0.0 ... instead
>>> >> of (what I would get from SAS) of NA (or in the case of
>>> >> SAS ".").
>>> >>
>>> >> Accordingly, I've had to go to 'extreme' measures to get
>>> >> the sum function to result in NA if all arguments are
>>> >> missing (otherwise give me a sum of all non-NA elements).
>>> >>
>>> >> So for example here's a snippet of code that ALMOST does
>>> >> what I want:
>>> >>
>>> >>
>>> >>
>>> SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2),
>>> >> select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE)
>>> >>
>>> >> In reality this does NOT give me records with NA for
>>> >> SumValue ... but it doesn't give me values for any
>>> >> records in which both Variable.1 and Variable.2 are NA
>>> >> --- which is "good enough" for my purposes.
>>> >>
>>> >> I'm guessing with a little more work I could come up with
>>> >> a way to adapt the code above so that I could get it to
>>> >> work like SAS's sum function ...
>>> >>
>>> >> ... but before I go that extra mile I thought I'd ask
>>> >> others if they know of functions in either base R ... or
>>> >> in a package that will better mimic the SAS sum function.
>>> >>
>>> >> Any suggestions?
>>> >>
>>> >> Thanks. __ Allen
>>> >> Bingham aebingh...@gmail.com
>>> >>
>>> >> __
>>> >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and
>>> >> more, see 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.
>>>
>>> > __
>>> > R-help@r-project.org mailing list -- To UNSUBSCRIBE and
>>> > more, see 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.
>>>
>>> __
>>> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
>>> 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.
>>>
>>
>> --
>> Hervé Pagès
>>
>> Program in Computational Biology
>> Division of Public Health Sciences
>> Fred Hutchinson Cancer Research Center
>> 1100 Fairview Ave. N, M1-B514
>> P.O. Box 19024
>> Seattle, WA 98109-1024
>>
>> E-mail: hpa...@fredhutch.org
>> Phone: (206) 667-5791
>> Fax:(206) 667-1319
>>
>> __
>> R-help@r-project.org
Re: [R] Sum function and missing values --- need to mimic SAS sum function
Huh?? > ifelse(TRUE, a <- 2L, a <- 3L) [1] 2 > a [1] 2 Please clarify. -- Bert Bert Gunter Genentech Nonclinical Biostatistics (650) 467-7374 "Data is not information. Information is not knowledge. And knowledge is certainly not wisdom." Clifford Stoll On Mon, Jan 26, 2015 at 2:22 PM, Hervé Pagès wrote: > Hi Martin, > > On 01/26/2015 04:45 AM, Martin Maechler wrote: >>> >>> Jim Lemon >>> on Mon, 26 Jan 2015 11:21:03 +1100 writes: >> >> >> > Hi Allen, How about this: >> >> > sum_w_NA<-function(x) ifelse(all(is.na(x)),NA,sum(x,na.rm=TRUE)) >> >> Excuse, Jim, but that's yet another "horrible misuse of ifelse()" >> >> John Fox's reply *did* contain the "proper" solution >> >> if (all(is.na(x))) NA else sum(x, na.rm=TRUE) >> >> The ifelse() function should never be used in such cases. >> Read more after googling >> >> "Do NOT use ifelse()" >> >> -- include the quotes in your search -- >> >> or directly at >> http://stat.ethz.ch/pipermail/r-help/2014-December/424367.html > > > Interesting. You could have added the following item to your list: > > 4. less likely to play strange tricks on you: > > > ifelse(TRUE, a <- 2L, a <- 3L) > [1] 2 > > a > [1] 3 > > Yeah I've seen people using ifelse() that way and being totally > confused... > > Cheers, > H. > >> >> Yes, this has been on R-help a month ago.. >> Martin >> >> > On Mon, Jan 26, 2015 at 10:21 AM, Allen Bingham >> > wrote: >> >> I understand that in order to get the sum function to >> >> ignore missing values I need to supply the argument >> >> na.rm=TRUE. However, when summing numeric values in which >> >> ALL components are "NA" ... the result is 0.0 ... instead >> >> of (what I would get from SAS) of NA (or in the case of >> >> SAS "."). >> >> >> >> Accordingly, I've had to go to 'extreme' measures to get >> >> the sum function to result in NA if all arguments are >> >> missing (otherwise give me a sum of all non-NA elements). >> >> >> >> So for example here's a snippet of code that ALMOST does >> >> what I want: >> >> >> >> >> >> >> SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2), >> >> select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE) >> >> >> >> In reality this does NOT give me records with NA for >> >> SumValue ... but it doesn't give me values for any >> >> records in which both Variable.1 and Variable.2 are NA >> >> --- which is "good enough" for my purposes. >> >> >> >> I'm guessing with a little more work I could come up with >> >> a way to adapt the code above so that I could get it to >> >> work like SAS's sum function ... >> >> >> >> ... but before I go that extra mile I thought I'd ask >> >> others if they know of functions in either base R ... or >> >> in a package that will better mimic the SAS sum function. >> >> >> >> Any suggestions? >> >> >> >> Thanks. __ Allen >> >> Bingham aebingh...@gmail.com >> >> >> >> __ >> >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and >> >> more, see 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. >> >> > __ >> > R-help@r-project.org mailing list -- To UNSUBSCRIBE and >> > more, see 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. >> >> __ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> 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. >> > > -- > Hervé Pagès > > Program in Computational Biology > Division of Public Health Sciences > Fred Hutchinson Cancer Research Center > 1100 Fairview Ave. N, M1-B514 > P.O. Box 19024 > Seattle, WA 98109-1024 > > E-mail: hpa...@fredhutch.org > Phone: (206) 667-5791 > Fax:(206) 667-1319 > > __ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read th
Re: [R] Sum function and missing values --- need to mimic SAS sum function
Hi Martin, On 01/26/2015 04:45 AM, Martin Maechler wrote: Jim Lemon on Mon, 26 Jan 2015 11:21:03 +1100 writes: > Hi Allen, How about this: > sum_w_NA<-function(x) ifelse(all(is.na(x)),NA,sum(x,na.rm=TRUE)) Excuse, Jim, but that's yet another "horrible misuse of ifelse()" John Fox's reply *did* contain the "proper" solution if (all(is.na(x))) NA else sum(x, na.rm=TRUE) The ifelse() function should never be used in such cases. Read more after googling "Do NOT use ifelse()" -- include the quotes in your search -- or directly at http://stat.ethz.ch/pipermail/r-help/2014-December/424367.html Interesting. You could have added the following item to your list: 4. less likely to play strange tricks on you: > ifelse(TRUE, a <- 2L, a <- 3L) [1] 2 > a [1] 3 Yeah I've seen people using ifelse() that way and being totally confused... Cheers, H. Yes, this has been on R-help a month ago.. Martin > On Mon, Jan 26, 2015 at 10:21 AM, Allen Bingham > wrote: >> I understand that in order to get the sum function to >> ignore missing values I need to supply the argument >> na.rm=TRUE. However, when summing numeric values in which >> ALL components are "NA" ... the result is 0.0 ... instead >> of (what I would get from SAS) of NA (or in the case of >> SAS "."). >> >> Accordingly, I've had to go to 'extreme' measures to get >> the sum function to result in NA if all arguments are >> missing (otherwise give me a sum of all non-NA elements). >> >> So for example here's a snippet of code that ALMOST does >> what I want: >> >> >> SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2), >> select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE) >> >> In reality this does NOT give me records with NA for >> SumValue ... but it doesn't give me values for any >> records in which both Variable.1 and Variable.2 are NA >> --- which is "good enough" for my purposes. >> >> I'm guessing with a little more work I could come up with >> a way to adapt the code above so that I could get it to >> work like SAS's sum function ... >> >> ... but before I go that extra mile I thought I'd ask >> others if they know of functions in either base R ... or >> in a package that will better mimic the SAS sum function. >> >> Any suggestions? >> >> Thanks. __ Allen >> Bingham aebingh...@gmail.com >> >> __ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and >> more, see 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. > __ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and > more, see 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. __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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. -- Hervé Pagès Program in Computational Biology Division of Public Health Sciences Fred Hutchinson Cancer Research Center 1100 Fairview Ave. N, M1-B514 P.O. Box 19024 Seattle, WA 98109-1024 E-mail: hpa...@fredhutch.org Phone: (206) 667-5791 Fax:(206) 667-1319 __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
On 27/01/15 13:42, Boris Steipe wrote: sum(x, na.rm=!all(is.na(x))) That's the kind of idiom that brings the poor chap who has to maintain it to tears. ;-) It looks perfectly lucid to me. If you think that that's obscure code, you ain't been around! :-) cheers, Rolf Turner -- Rolf Turner Technical Editor ANZJS Department of Statistics University of Auckland Phone: +64-9-373-7599 ext. 88276 Home phone: +64-9-480-4619 __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
> sum(x, na.rm=!all(is.na(x))) That's the kind of idiom that brings the poor chap who has to maintain it to tears. ;-) __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
Sven and John, Thanks for your suggested code ... hits the mark! The code by John is what I need to be able to use in an apply function, but I really like the simplicity of Sven's suggestion. Also thanks to all who replied --- really helped broaden my knowledge of R. Allen -Original Message- From: Sven E. Templer [mailto:sven.temp...@gmail.com] Sent: Monday, January 26, 2015 6:56 AM To: Martin Maechler Cc: Jim Lemon; r-help mailing list; Allen Bingham Subject: Re: [R] Sum function and missing values --- need to mimic SAS sum function you can also define 'na.rm' in sum() by 'NA state' of x (where x is your vector holding the data): sum(x, na.rm=!all(is.na(x))) On 26 January 2015 at 13:45, Martin Maechler wrote: >>>>>> Jim Lemon >>>>>> on Mon, 26 Jan 2015 11:21:03 +1100 writes: > > > Hi Allen, How about this: > > > sum_w_NA<-function(x) ifelse(all(is.na(x)),NA,sum(x,na.rm=TRUE)) > > Excuse, Jim, but that's yet another "horrible misuse of ifelse()" > > John Fox's reply *did* contain the "proper" solution > > if (all(is.na(x))) NA else sum(x, na.rm=TRUE) > > The ifelse() function should never be used in such cases. > Read more after googling > > "Do NOT use ifelse()" > > -- include the quotes in your search -- > > or directly at >http://stat.ethz.ch/pipermail/r-help/2014-December/424367.html > > Yes, this has been on R-help a month ago.. > Martin > > > On Mon, Jan 26, 2015 at 10:21 AM, Allen Bingham > > wrote: > >> I understand that in order to get the sum function to > >> ignore missing values I need to supply the argument > >> na.rm=TRUE. However, when summing numeric values in which > >> ALL components are "NA" ... the result is 0.0 ... instead > >> of (what I would get from SAS) of NA (or in the case of > >> SAS "."). > >> > >> Accordingly, I've had to go to 'extreme' measures to get > >> the sum function to result in NA if all arguments are > >> missing (otherwise give me a sum of all non-NA elements). > >> > >> So for example here's a snippet of code that ALMOST does > >> what I want: > >> > >> > >> > SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2), > >> select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE) > >> > >> In reality this does NOT give me records with NA for > >> SumValue ... but it doesn't give me values for any > >> records in which both Variable.1 and Variable.2 are NA > >> --- which is "good enough" for my purposes. > >> > >> I'm guessing with a little more work I could come up with > >> a way to adapt the code above so that I could get it to > >> work like SAS's sum function ... > >> > >> ... but before I go that extra mile I thought I'd ask > >> others if they know of functions in either base R ... or > >> in a package that will better mimic the SAS sum function. > >> > >> Any suggestions? > >> > >> Thanks. __ Allen > >> Bingham aebingh...@gmail.com > >> > >> __ > >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and > >> more, see 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. > > > __ > > R-help@r-project.org mailing list -- To UNSUBSCRIBE and > > more, see 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. > > __ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
Don, The default for the sum function is to NOT remove NA before summing (i.e., option na.rm=FALSE), here's the results with na.rm=TRUE > sum(NA,na.rm=TRUE) [1] 0 > sum(c(NA,NA),na.rm=TRUE) [1] 0 > sum(rep(NA,10),na.rm=TRUE) [1] 0 > sum(as.numeric(letters[1:4]),na.rm=TRUE) [1] 0 Warning message: NAs introduced by coercion Hope that explains it a bit better. Others have replied with suggested solutions to my 'problem', and the one by John Fox is what I need (an actual function that I can use in an apply statement), although the suggested code by Sven Templer is appealing in its simplicity. Allen -Original Message- From: MacQueen, Don [mailto:macque...@llnl.gov] Sent: Monday, January 26, 2015 1:03 PM To: Allen Bingham; r-help@r-project.org Subject: Re: [R] Sum function and missing values --- need to mimic SAS sum function I'm a little puzzled by the assertion that the result is 0.0 when all the elements are NA: > sum(NA) [1] NA > sum(c(NA,NA)) [1] NA > sum(rep(NA, 10)) [1] NA > sum(as.numeric(letters[1:4])) [1] NA Warning message: NAs introduced by coercion Considering that the example snippet of code has several other aspects besides using sum(), among them subsetting rows of a data frame when there are apparently NAs in some its variables ... I wonder if the reason for the failure of that snippet has been misunderstood? -- Don MacQueen Lawrence Livermore National Laboratory 7000 East Ave., L-627 Livermore, CA 94550 925-423-1062 On 1/25/15, 3:21 PM, "Allen Bingham" wrote: >I understand that in order to get the sum function to ignore missing >values I need to supply the argument na.rm=TRUE. However, when summing >numeric values in which ALL components are "NA" ... the result is 0.0 >... instead of (what I would get from SAS) of NA (or in the case of SAS >"."). > >Accordingly, I've had to go to 'extreme' measures to get the sum >function to result in NA if all arguments are missing (otherwise give >me a sum of all non-NA elements). > >So for example here's a snippet of code that ALMOST does what I want: > > >SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variabl >e.2 >), >select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE) > >In reality this does NOT give me records with NA for SumValue ... but >it doesn't give me values for any records in which both Variable.1 and >Variable.2 are NA --- which is "good enough" for my purposes. > >I'm guessing with a little more work I could come up with a way to >adapt the code above so that I could get it to work like SAS's sum >function ... > >... but before I go that extra mile I thought I'd ask others if they >know of functions in either base R ... or in a package that will better >mimic the SAS sum function. > >Any suggestions? > >Thanks. >__ >Allen Bingham >aebingh...@gmail.com > >__ >R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >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. __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
In case anyone wonders, this behavior is expected and consistent with
the note "the sum of an empty set is zero, by definition" in
help("sum"), i.e.
> x <- numeric(0)
> str(x)
num(0)
> sum(x)
[1] 0
Analogously, prod(numeric(0)) gives 1.0.
To OP, if you're in the end of the day is after the sample mean, note
that mean() returns NaN in this case, e.g.
> x <- rep(NA_real_, times=10)
> mean(x, na.rm=TRUE)
[1] NaN
/Henrik
On Mon, Jan 26, 2015 at 1:17 PM, Ista Zahn wrote:
> Try with na.rm=TRUE.
> On Jan 26, 2015 4:04 PM, "MacQueen, Don" wrote:
>
>> I'm a little puzzled by the assertion that the result is 0.0 when all the
>> elements are NA:
>>
>> > sum(NA)
>> [1] NA
>>
>> > sum(c(NA,NA))
>> [1] NA
>>
>> > sum(rep(NA, 10))
>> [1] NA
>>
>> > sum(as.numeric(letters[1:4]))
>> [1] NA
>> Warning message:
>> NAs introduced by coercion
>>
>>
>> Considering that the example snippet of code has several other aspects
>> besides using sum(), among them subsetting rows of a data frame when there
>> are apparently NAs in some its variables ... I wonder if the reason for
>> the failure of that snippet has been misunderstood?
>>
>>
>> --
>> Don MacQueen
>>
>> Lawrence Livermore National Laboratory
>> 7000 East Ave., L-627
>> Livermore, CA 94550
>> 925-423-1062
>>
>>
>>
>>
>>
>> On 1/25/15, 3:21 PM, "Allen Bingham" wrote:
>>
>> >I understand that in order to get the sum function to ignore missing
>> >values
>> >I need to supply the argument na.rm=TRUE. However, when summing numeric
>> >values in which ALL components are "NA" ... the result is 0.0 ... instead
>> >of
>> >(what I would get from SAS) of NA (or in the case of SAS ".").
>> >
>> >Accordingly, I've had to go to 'extreme' measures to get the sum function
>> >to
>> >result in NA if all arguments are missing (otherwise give me a sum of all
>> >non-NA elements).
>> >
>> >So for example here's a snippet of code that ALMOST does what I want:
>> >
>> >
>> >SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na
>> (Variable.2
>> >),
>> >select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE)
>> >
>> >In reality this does NOT give me records with NA for SumValue ... but it
>> >doesn't give me values for any records in which both Variable.1 and
>> >Variable.2 are NA --- which is "good enough" for my purposes.
>> >
>> >I'm guessing with a little more work I could come up with a way to adapt
>> >the
>> >code above so that I could get it to work like SAS's sum function ...
>> >
>> >... but before I go that extra mile I thought I'd ask others if they know
>> >of
>> >functions in either base R ... or in a package that will better mimic the
>> >SAS sum function.
>> >
>> >Any suggestions?
>> >
>> >Thanks.
>> >__
>> >Allen Bingham
>> >aebingh...@gmail.com
>> >
>> >__
>> >R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> >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.
>>
>> __
>> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> 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.
>>
>
> [[alternative HTML version deleted]]
>
> __
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
Try with na.rm=TRUE. On Jan 26, 2015 4:04 PM, "MacQueen, Don" wrote: > I'm a little puzzled by the assertion that the result is 0.0 when all the > elements are NA: > > > sum(NA) > [1] NA > > > sum(c(NA,NA)) > [1] NA > > > sum(rep(NA, 10)) > [1] NA > > > sum(as.numeric(letters[1:4])) > [1] NA > Warning message: > NAs introduced by coercion > > > Considering that the example snippet of code has several other aspects > besides using sum(), among them subsetting rows of a data frame when there > are apparently NAs in some its variables ... I wonder if the reason for > the failure of that snippet has been misunderstood? > > > -- > Don MacQueen > > Lawrence Livermore National Laboratory > 7000 East Ave., L-627 > Livermore, CA 94550 > 925-423-1062 > > > > > > On 1/25/15, 3:21 PM, "Allen Bingham" wrote: > > >I understand that in order to get the sum function to ignore missing > >values > >I need to supply the argument na.rm=TRUE. However, when summing numeric > >values in which ALL components are "NA" ... the result is 0.0 ... instead > >of > >(what I would get from SAS) of NA (or in the case of SAS "."). > > > >Accordingly, I've had to go to 'extreme' measures to get the sum function > >to > >result in NA if all arguments are missing (otherwise give me a sum of all > >non-NA elements). > > > >So for example here's a snippet of code that ALMOST does what I want: > > > > > >SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na > (Variable.2 > >), > >select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE) > > > >In reality this does NOT give me records with NA for SumValue ... but it > >doesn't give me values for any records in which both Variable.1 and > >Variable.2 are NA --- which is "good enough" for my purposes. > > > >I'm guessing with a little more work I could come up with a way to adapt > >the > >code above so that I could get it to work like SAS's sum function ... > > > >... but before I go that extra mile I thought I'd ask others if they know > >of > >functions in either base R ... or in a package that will better mimic the > >SAS sum function. > > > >Any suggestions? > > > >Thanks. > >__ > >Allen Bingham > >aebingh...@gmail.com > > > >__ > >R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > >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. > > __ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. > [[alternative HTML version deleted]] __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
I'm a little puzzled by the assertion that the result is 0.0 when all the elements are NA: > sum(NA) [1] NA > sum(c(NA,NA)) [1] NA > sum(rep(NA, 10)) [1] NA > sum(as.numeric(letters[1:4])) [1] NA Warning message: NAs introduced by coercion Considering that the example snippet of code has several other aspects besides using sum(), among them subsetting rows of a data frame when there are apparently NAs in some its variables ... I wonder if the reason for the failure of that snippet has been misunderstood? -- Don MacQueen Lawrence Livermore National Laboratory 7000 East Ave., L-627 Livermore, CA 94550 925-423-1062 On 1/25/15, 3:21 PM, "Allen Bingham" wrote: >I understand that in order to get the sum function to ignore missing >values >I need to supply the argument na.rm=TRUE. However, when summing numeric >values in which ALL components are "NA" ... the result is 0.0 ... instead >of >(what I would get from SAS) of NA (or in the case of SAS "."). > >Accordingly, I've had to go to 'extreme' measures to get the sum function >to >result in NA if all arguments are missing (otherwise give me a sum of all >non-NA elements). > >So for example here's a snippet of code that ALMOST does what I want: > > >SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2 >), >select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE) > >In reality this does NOT give me records with NA for SumValue ... but it >doesn't give me values for any records in which both Variable.1 and >Variable.2 are NA --- which is "good enough" for my purposes. > >I'm guessing with a little more work I could come up with a way to adapt >the >code above so that I could get it to work like SAS's sum function ... > >... but before I go that extra mile I thought I'd ask others if they know >of >functions in either base R ... or in a package that will better mimic the >SAS sum function. > >Any suggestions? > >Thanks. >__ >Allen Bingham >aebingh...@gmail.com > >__ >R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >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. __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
you can also define 'na.rm' in sum() by 'NA state' of x (where x is your vector holding the data): sum(x, na.rm=!all(is.na(x))) On 26 January 2015 at 13:45, Martin Maechler wrote: >> Jim Lemon >> on Mon, 26 Jan 2015 11:21:03 +1100 writes: > > > Hi Allen, How about this: > > > sum_w_NA<-function(x) ifelse(all(is.na(x)),NA,sum(x,na.rm=TRUE)) > > Excuse, Jim, but that's yet another "horrible misuse of ifelse()" > > John Fox's reply *did* contain the "proper" solution > > if (all(is.na(x))) NA else sum(x, na.rm=TRUE) > > The ifelse() function should never be used in such cases. > Read more after googling > > "Do NOT use ifelse()" > > -- include the quotes in your search -- > > or directly at >http://stat.ethz.ch/pipermail/r-help/2014-December/424367.html > > Yes, this has been on R-help a month ago.. > Martin > > > On Mon, Jan 26, 2015 at 10:21 AM, Allen Bingham > > wrote: > >> I understand that in order to get the sum function to > >> ignore missing values I need to supply the argument > >> na.rm=TRUE. However, when summing numeric values in which > >> ALL components are "NA" ... the result is 0.0 ... instead > >> of (what I would get from SAS) of NA (or in the case of > >> SAS "."). > >> > >> Accordingly, I've had to go to 'extreme' measures to get > >> the sum function to result in NA if all arguments are > >> missing (otherwise give me a sum of all non-NA elements). > >> > >> So for example here's a snippet of code that ALMOST does > >> what I want: > >> > >> > >> > SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2), > >> select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE) > >> > >> In reality this does NOT give me records with NA for > >> SumValue ... but it doesn't give me values for any > >> records in which both Variable.1 and Variable.2 are NA > >> --- which is "good enough" for my purposes. > >> > >> I'm guessing with a little more work I could come up with > >> a way to adapt the code above so that I could get it to > >> work like SAS's sum function ... > >> > >> ... but before I go that extra mile I thought I'd ask > >> others if they know of functions in either base R ... or > >> in a package that will better mimic the SAS sum function. > >> > >> Any suggestions? > >> > >> Thanks. __ Allen > >> Bingham aebingh...@gmail.com > >> > >> __ > >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and > >> more, see 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. > > > __ > > R-help@r-project.org mailing list -- To UNSUBSCRIBE and > > more, see 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. > > __ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
> Jim Lemon > on Mon, 26 Jan 2015 11:21:03 +1100 writes: > Hi Allen, How about this: > sum_w_NA<-function(x) ifelse(all(is.na(x)),NA,sum(x,na.rm=TRUE)) Excuse, Jim, but that's yet another "horrible misuse of ifelse()" John Fox's reply *did* contain the "proper" solution if (all(is.na(x))) NA else sum(x, na.rm=TRUE) The ifelse() function should never be used in such cases. Read more after googling "Do NOT use ifelse()" -- include the quotes in your search -- or directly at http://stat.ethz.ch/pipermail/r-help/2014-December/424367.html Yes, this has been on R-help a month ago.. Martin > On Mon, Jan 26, 2015 at 10:21 AM, Allen Bingham > wrote: >> I understand that in order to get the sum function to >> ignore missing values I need to supply the argument >> na.rm=TRUE. However, when summing numeric values in which >> ALL components are "NA" ... the result is 0.0 ... instead >> of (what I would get from SAS) of NA (or in the case of >> SAS "."). >> >> Accordingly, I've had to go to 'extreme' measures to get >> the sum function to result in NA if all arguments are >> missing (otherwise give me a sum of all non-NA elements). >> >> So for example here's a snippet of code that ALMOST does >> what I want: >> >> >> SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2), >> select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE) >> >> In reality this does NOT give me records with NA for >> SumValue ... but it doesn't give me values for any >> records in which both Variable.1 and Variable.2 are NA >> --- which is "good enough" for my purposes. >> >> I'm guessing with a little more work I could come up with >> a way to adapt the code above so that I could get it to >> work like SAS's sum function ... >> >> ... but before I go that extra mile I thought I'd ask >> others if they know of functions in either base R ... or >> in a package that will better mimic the SAS sum function. >> >> Any suggestions? >> >> Thanks. __ Allen >> Bingham aebingh...@gmail.com >> >> __ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and >> more, see 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. > __ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and > more, see 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. __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
Ouch. Please avoid ifelse() in non-vectorized contexts. John Fox has the right idea. -pd On 26 Jan 2015, at 01:21 , Jim Lemon wrote: > Hi Allen, > How about this: > > sum_w_NA<-function(x) ifelse(all(is.na(x)),NA,sum(x,na.rm=TRUE)) > > Jim > > > On Mon, Jan 26, 2015 at 10:21 AM, Allen Bingham wrote: >> I understand that in order to get the sum function to ignore missing values >> I need to supply the argument na.rm=TRUE. However, when summing numeric >> values in which ALL components are "NA" ... the result is 0.0 ... instead of >> (what I would get from SAS) of NA (or in the case of SAS "."). >> >> Accordingly, I've had to go to 'extreme' measures to get the sum function to >> result in NA if all arguments are missing (otherwise give me a sum of all >> non-NA elements). >> >> So for example here's a snippet of code that ALMOST does what I want: >> >> >> SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2), >> select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE) >> >> In reality this does NOT give me records with NA for SumValue ... but it >> doesn't give me values for any records in which both Variable.1 and >> Variable.2 are NA --- which is "good enough" for my purposes. >> >> I'm guessing with a little more work I could come up with a way to adapt the >> code above so that I could get it to work like SAS's sum function ... >> >> ... but before I go that extra mile I thought I'd ask others if they know of >> functions in either base R ... or in a package that will better mimic the >> SAS sum function. >> >> Any suggestions? >> >> Thanks. >> __ >> Allen Bingham >> aebingh...@gmail.com >> >> __ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> 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. > > __ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. -- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Email: pd@cbs.dk Priv: pda...@gmail.com __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
Hi Allen, How about this: sum_w_NA<-function(x) ifelse(all(is.na(x)),NA,sum(x,na.rm=TRUE)) Jim On Mon, Jan 26, 2015 at 10:21 AM, Allen Bingham wrote: > I understand that in order to get the sum function to ignore missing values > I need to supply the argument na.rm=TRUE. However, when summing numeric > values in which ALL components are "NA" ... the result is 0.0 ... instead of > (what I would get from SAS) of NA (or in the case of SAS "."). > > Accordingly, I've had to go to 'extreme' measures to get the sum function to > result in NA if all arguments are missing (otherwise give me a sum of all > non-NA elements). > > So for example here's a snippet of code that ALMOST does what I want: > > > SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2), > select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE) > > In reality this does NOT give me records with NA for SumValue ... but it > doesn't give me values for any records in which both Variable.1 and > Variable.2 are NA --- which is "good enough" for my purposes. > > I'm guessing with a little more work I could come up with a way to adapt the > code above so that I could get it to work like SAS's sum function ... > > ... but before I go that extra mile I thought I'd ask others if they know of > functions in either base R ... or in a package that will better mimic the > SAS sum function. > > Any suggestions? > > Thanks. > __ > Allen Bingham > aebingh...@gmail.com > > __ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Re: [R] Sum function and missing values --- need to mimic SAS sum function
Dear Allen,
This seems reasonably straightforward to me, suggesting that I might not
properly understand what you want to do. How about something like the following?
> mysum <- function(...){
+ x <- c(...)
+ if (all(is.na(x))) NA else sum(x, na.rm=TRUE)
+ }
> mysum(1, 2, 3, NA)
[1] 6
> mysum(1:3)
[1] 6
> mysum(NA, NA, NA)
[1] NA
> mysum(c(NA, NA, NA))
[1] NA
I hope this helps,
John
John Fox, Professor
McMaster University
Hamilton, Ontario, Canada
http://socserv.mcmaster.ca/jfox/
On Sun, 25 Jan 2015 15:21:52 -0800
"Allen Bingham" wrote:
> I understand that in order to get the sum function to ignore missing values
> I need to supply the argument na.rm=TRUE. However, when summing numeric
> values in which ALL components are "NA" ... the result is 0.0 ... instead of
> (what I would get from SAS) of NA (or in the case of SAS ".").
>
> Accordingly, I've had to go to 'extreme' measures to get the sum function to
> result in NA if all arguments are missing (otherwise give me a sum of all
> non-NA elements).
>
> So for example here's a snippet of code that ALMOST does what I want:
>
>
> SumValue<-apply(subset(InputDataFrame,!is.na(Variable.1)|!is.na(Variable.2),
> select=c(Variable.1,Variable.2)),1,sum,na.rm=TRUE)
>
> In reality this does NOT give me records with NA for SumValue ... but it
> doesn't give me values for any records in which both Variable.1 and
> Variable.2 are NA --- which is "good enough" for my purposes.
>
> I'm guessing with a little more work I could come up with a way to adapt the
> code above so that I could get it to work like SAS's sum function ...
>
> ... but before I go that extra mile I thought I'd ask others if they know of
> functions in either base R ... or in a package that will better mimic the
> SAS sum function.
>
> Any suggestions?
>
> Thanks.
> __
> Allen Bingham
> aebingh...@gmail.com
>
> __
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.
