Please delete drjimle...@bitwrit.com from your mailing list. He passed away a month ago. Regards, Juel (wife)
On Thu, 19 Oct 2023, 02:09 Ben Bolker <bbol...@gmail.com wrote: > There are some answers on Stack Overflow: > > > https://stackoverflow.com/questions/14984989/how-to-avoid-warning-when-introducing-nas-by-coercion > > > > On 2023-10-18 10:59 a.m., Leonard Mada via R-help wrote: > > Dear List members, > > > > What is the best way to test for numeric digits? > > > > suppressWarnings(as.double(c("Li", "Na", "K", "2", "Rb", "Ca", "3"))) > > # [1] NA NA NA 2 NA NA 3 > > The above requires the use of the suppressWarnings function. Are there > > any better ways? > > > > I was working to extract chemical elements from a formula, something > > like this: > > split.symbol.character = function(x, rm.digits = TRUE) { > > # Perl is partly broken in R 4.3, but this works: > > regex = > "(?<=[A-Z])(?![a-z]|$)|(?<=.)(?=[A-Z])|(?<=[a-z])(?=[^a-z])"; > > # stringi::stri_split(x, regex = regex); > > s = strsplit(x, regex, perl = TRUE); > > if(rm.digits) { > > s = lapply(s, function(s) { > > isNotD = is.na(suppressWarnings(as.numeric(s))); > > s = s[isNotD]; > > }); > > } > > return(s); > > } > > > > split.symbol.character(c("CCl3F", "Li4Al4H16", "CCl2CO2AlPO4SiO4Cl")) > > > > > > Sincerely, > > > > > > Leonard > > > > > > Note: > > # works: > > regex = "(?<=[A-Z])(?![a-z]|$)|(?<=.)(?=[A-Z])|(?<=[a-z])(?=[^a-z])"; > > strsplit(c("CCl3F", "Li4Al4H16", "CCl2CO2AlPO4SiO4Cl"), regex, perl = T) > > > > > > # broken in R 4.3.1 > > # only slightly "erroneous" with stringi::stri_split > > regex = "(?<=[A-Z])(?![a-z]|$)|(?=[A-Z])|(?<=[a-z])(?=[^a-z])"; > > strsplit(c("CCl3F", "Li4Al4H16", "CCl2CO2AlPO4SiO4Cl"), regex, perl = T) > > > > ______________________________________________ > > 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.
