similar to: integer(0) and NA do not equal FALSE

Dear R wizes, I have a data.frame of species abundances with column names consisting of 4 letter codes then an underscore and a number like this: abco_1, abco_2, abco_3, psm_1, psme_2, psme_3, etc. I would like to get an identifier for all the abco, and psme and other species etc. I used spec.fact<-substring(names(spec.count),1,4) To make a vector of the first 4 letters of

Last one for you guys: The command: length(gregexpr('cus','hocus pocus')[[1]]) [1] 2 returns the number of times the substring 'cus' appears in 'hocus pocus' (which is two) It's returning the number of **disjoint** matches. So: length(gregexpr('aa','aaa')[[1]]) [1] 1 returns 1. **What I want to do:** I'm looking for a way to count

I observed the following: match.arg("white", colors()) yields 'white', but match.arg("whit", colors()) yields: `Error in match.arg("whit", colors()) : 'arg' should be one of "white", "aliceblue", '... this message actually comes from `pmatch'. using a suitable subset of `colors()' works OK. the precise length

The pmatch help (see also section 4.3.2 in the R Language Definition) claims that pmatch with duplicates.ok=FALSE provides the same functionality as R's argument matching algorithm, modulo how empty strings are matched. Here's an undocumented inconsistency between pmatch and R's argument matching algorithm: > sessionInfo() R version 3.0.1 (2013-05-16) Platform:

On Wed, 13 Dec 2023 09:04:18 +0100 Hilmar Berger via R-devel <r-devel at r-project.org> wrote: > Still, I feel that default partial matching cripples the functionality > of data.frame for larger tables. Changing the default now would require a long deprecation cycle to give everyone who uses `[.data.frame` and relies on partial matching (whether they know it or not) enough time to

Hi Hilmar and Ivan, I have used your code examples to write a blog post about this topic, which has figures that show the asymptotic time complexity of the various approaches, https://tdhock.github.io/blog/2023/df-partial-match/ The asymptotic complexity of partial matching appears to be quadratic O(N^2) whereas the other approaches are asymptotically faster: linear O(N) or log-linear O(N log N).

Hi folks, Can anyone suggest an efficient way to do "matching without replacement", or "one-to-one matching"? pmatch() doesn't quite provide what I need... For example, lookupTable <- c("a","b","c","d","e","f") matchSample <- c("a","a","b","d") ##Normal match()

I am using R0.64.1 under Windows 95. The help for `pmatch' states that: If `duplicates.ok' is false multiple matches will result in the value of `nomatch' being returned, and if it is true, the index of the first matching value will be returned. The help for pmatch gives the following examples: pmatch("m", c("mean",

On Aug 28, 2009, at 1:53 AM, Daniel Dunbar wrote: > Nice! > > This looks good to me but probably Chris or someone else should sign > off on it. This seems ok to me, please commit. One minor comment: +++ b/lib/Support/Regex.cpp + // Allocate pmatch with at least one element. + pmatch = new llvm_regmatch_t[nmatch > 0 ? nmatch : 1]; + pmatch[0].rm_so = 0; + pmatch[0].rm_eo =

Dear R, the condition: identical(length(x),1) returns FALSE but print(length(x)) returns 1 and: is.vector(x) is TRUE. is.integer(length(x)) is TRUE length(x) ==1 is TRUE I am puzzled. Regards -- Corrado Topi Global Climate Change & Biodiversity Indicators Area 18,Department of Biology University of York, York, YO10 5YW, UK Phone: + 44 (0) 1904 328645, E-mail: ct529 at york.ac.uk

Hello, Is there a function for searching a string for a given character? For example, I have transcriptions like tsibi tSibi tibi kibi I want to search the character object for the presence of 's' or 'S' or 'k'. I thought perhaps pmatch(c("k", "S", "s"), x) would work for me, but it wants to compare from the start of the string and returns

I'm using R 1.6.1 on Windows 95 with cygwin bash as my shell. The 'shell' command tries to determine which shell the user prefers via the following steps: shell <- Sys.getenv("R_SHELL") if (!nchar(shell)) shell <- Sys.getenv("SHELL") if (!nchar(shell)) shell <- Sys.getenv("COMSPEC") For me, shell

Hi all, This occurred in R-2.11.0 (WinXP). The R-help page of .[ says that: "Character indices can in some circumstances be partially matched (see pmatch) to the names or dimnames of the object being subsetted (but never for subassignment). Unlike S (Becker et al p. 358)), R has never used partial matching when extracting by [, and as from R 2.7.0 partial matching is not by default used by

Hi, I have the following error when building a package * creating vignettes ... ERROR Error: chunk 3 Error in pmatch(x, table, duplicates.ok) : argument is not of mode character Error in buildVignettes(dir = ".") : Error: chunk 3 Error in pmatch(x, table, duplicates.ok) : argument is not of mode character Execution halted I use R-2.0.1 under debian linux 2.6.9

Hello R Helpers, Business - 64 bit windows 7, R 2.11.1 I am trying to match the character contents of one list, called 'exclude', to those of a second list, called 'dataset' dataset is a list of file names with folder locations, and looks like this when called: > dataset [1] "A/10-10-29a-13.cdf" "A/10-10-29a-14.cdf" "A/10-10-29a-15.cdf"

Hi R users, I am trying to omit rows of data based on partial matches an example of my data (seal_dist) is below: A quick break down of my coding and why I need to answer this - I am dealing with a colony of seals where for example A1 is a female with pup and A1.1 is that female's pup, the important part of the data here is DIST which tells the distance between one seal (ID) and another

Hi, I have a buster system configured as a DC running 4.11.13 from Louis's repo. I am trying to get https://wiki.samba.org/index.php/Configure_DHCP_to_update_DNS_records_with_BIND9 working. Mostly it seems to work but there seems to be a problem with what dhcpd writes into the leases file in the "on release" stanza. When dhcpd writes the On Release stanza I get something like the

the first line of dist() says if (!is.na(pmatch(method, "euclidian"))) shouldn't that be "euclidean" ? --------------------- R version 2.5.1 (2007-06-27) i486-pc-linux-gnu locale:

Hi, I wonder if there's a good intro to the pattern matching using R? I'm a perl programer and find it too confusing and complex to use regular expressions under R. For instance, why does pmatch("d","ad") returns NULL? How would I call the functions in order to match any portion of the string? Under what circumstances shall backslush be used? I try to extract all

On 2/20/19 7:55 PM, Toby Hocking wrote: > Update: I have observed that stringi::stri_sub is linear time complexity, > and it computes the same thing as base::substring. figure > https://github.com/tdhock/namedCapture-article/blob/master/figure-substring-bug.png > source: > https://github.com/tdhock/namedCapture-article/blob/master/figure-substring-bug.R > > To me this is a