I tend to avoid using as.<type> functions on lists, since they act oddly in several ways. E.g, if the list "L" consists entirely of scalar elements then as.numeric(L) acts like as.numeric(unlist(L)) but if any element is not a scalar there is an error. as.character() does not seem to make a distinction between the all-scalar and not-all-scalar cases but does various things with NA's of various types.
Bill Dunlap TIBCO Software wdunlap tibco.com On Mon, Jan 22, 2018 at 11:14 AM, Robert McGehee < rmcge...@walleyetrading.net> wrote: > Also perhaps a surprise that the behavior depends on the mode of the NA. > > > is.na(as.character(list(NA_real_))) > [1] FALSE > > is.na(as.character(list(NA_character_))) > [1] TRUE > > Does this mean deparse() preserves NA-ness for NA_character_ but not > NA_real_? > > > -----Original Message----- > From: R-devel [mailto:r-devel-boun...@r-project.org] On Behalf Of Hervé > Pagès > Sent: Monday, January 22, 2018 2:01 PM > To: William Dunlap <wdun...@tibco.com>; Patrick Perry < > ppe...@stern.nyu.edu> > Cc: r-devel@r-project.org > Subject: Re: [Rd] as.character(list(NA)) > > On 01/20/2018 08:24 AM, William Dunlap via R-devel wrote: > > I believe that for a list as.character() applies deparse() to each > element > > of the list. deparse() does not preserve NA-ness, as it is intended to > > make text that the parser can read. > > > >> str(as.character(list(Na=NA, LglVec=c(TRUE,NA), > > Function=function(x){x+1}))) > > chr [1:3] "NA" "c(TRUE, NA)" "function (x) \n{\n x + 1\n}" > > > > This really comes as a surprise though since coercion to all the > other atomic types (except raw) preserve the NAs. > > And also as.character(unlist(list(NA))) preserves them. > > H. > > > > > Bill Dunlap > > TIBCO Software > > wdunlap tibco.com > > > > On Sat, Jan 20, 2018 at 7:43 AM, Patrick Perry <ppe...@stern.nyu.edu> > wrote: > > > >> As of R Under development (unstable) (2018-01-19 r74138): > >> > >>> as.character(list(NA)) > >> [1] "NA" > >> > >>> is.na(as.character(list(NA))) > >> [1] FALSE > >> > >> ______________________________________________ > >> R-devel@r-project.org mailing list > >> https://urldefense.proofpoint.com/v2/url?u=https-3A__stat. > ethz.ch_mailman_listinfo_r-2Ddevel&d=DwICAg&c=eRAMFD45gAfqt84VtBcfhQ&r= > BK7q3XeAvimeWdGbWY_wJYbW0WYiZvSXAJJKaaPhzWA&m= > VbamM9XRQOlfBakrmlrmQZ7DLgXZ-hhhFeLD-fKpoCo&s= > Luhqwpr2bTltIA9Cy7kA4gwcQh16bla0S6OVe3Z09Xo&e= > >> > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > R-devel@r-project.org mailing list > > https://urldefense.proofpoint.com/v2/url?u=https-3A__stat. > ethz.ch_mailman_listinfo_r-2Ddevel&d=DwICAg&c=eRAMFD45gAfqt84VtBcfhQ&r= > BK7q3XeAvimeWdGbWY_wJYbW0WYiZvSXAJJKaaPhzWA&m= > VbamM9XRQOlfBakrmlrmQZ7DLgXZ-hhhFeLD-fKpoCo&s= > Luhqwpr2bTltIA9Cy7kA4gwcQh16bla0S6OVe3Z09Xo&e= > > > > -- > 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-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel > [[alternative HTML version deleted]] ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
