[R] & and |

Eric Berger er|cjberger @end|ng |rom gm@||@com
Wed Aug 19 17:17:34 CEST 2020


mydata[ intersect( grep("ConfoMap", mydata), grep("GuineaPigs", mydata)  ) ]



On Wed, Aug 19, 2020 at 6:13 PM Bert Gunter <bgunter.4567 using gmail.com> wrote:

> "&" is not a regex metacharacter.
> See ?regexp
>
> Bert Gunter
>
> "The trouble with having an open mind is that people keep coming along and
> sticking things into it."
> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
>
>
> On Wed, Aug 19, 2020 at 7:53 AM Ivan Calandra <calandra using rgzm.de> wrote:
>
> > Dear useRs,
> >
> > I feel really stupid, but I cannot understand why "&" doesn't work as I
> > expect, while "|" does.
> >
> > I have the following vector:
> > mydata <- c("SSFA-ConfoMap_GuineaPigs_NMPfilled.csv",
> > "SSFA-ConfoMap_Lithics_NMPfilled.csv",
> > "SSFA-ConfoMap_Sheeps_NMPfilled.csv", "SSFA-Toothfrax_GuineaPigs.xlsx",
> > "SSFA-Toothfrax_Lithics.xlsx", "SSFA-Toothfrax_Sheeps.xlsx")
> > and I want to find the values that include both "ConfoMap" and
> > "GuineaPigs".
> >
> > If I do:
> > grep("ConfoMap&GuineaPigs", mydata, value=TRUE)
> > it returns an empty vector, character(0).
> >
> > But if I do:
> > grep("ConfoMap|GuineaPigs", mydata, value=TRUE)
> > it returns all the elements that include either "ConfoMap" or
> > "GuineaPigs", as I would expect.
> >
> > So what is wrong with my "&" construct? How can I return the elements
> > that include both parts?
> >
> > Thank you for your help!
> > Ivan
> >
> > --
> > Dr. Ivan Calandra
> > TraCEr, laboratory for Traceology and Controlled Experiments
> > MONREPOS Archaeological Research Centre and
> > Museum for Human Behavioural Evolution
> > Schloss Monrepos
> > 56567 Neuwied, Germany
> > +49 (0) 2631 9772-243
> > https://www.researchgate.net/profile/Ivan_Calandra
> >
> > ______________________________________________
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> > PLEASE do read the posting guide
> > http://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
> >
>
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>
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
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> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

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