& and |

Thank you Bert for the pointer.

So I guess the solution is:
grep("ConfoMap.+GuineaPigs", mydata, value=TRUE)

This is not the case here, but what if "GuineaPigs" comes before
"ConfoMap"?
Of course I could do two "grep()" calls, but if there a better solution?

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

On 19/08/2020 17:07, Bert Gunter 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 at rgzm.de
<mailto:calandra at 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