[R] how to extract strings in any column and in any row that start with

[Ana Marija]

Hello,

this command was running for more than 2 hours
grep("E10",tot,value=T)
and no output

and this command
df1 <- tot %>% filter_all(any_vars(grepl( '^E10', .)))

gave me a subset (a data frame) of tot where ^E10

what I need is just a vector or all values in tot which start with E10.

Thanks
Ana

On Fri, May 15, 2020 at 12:13 PM Jeff Newmiller
<jdnewmil using dcn.davis.ca.us> wrote:
>
> Read about regular expressions... they are extremely useful.
>
> df1 <- tot %>% filter_all(any_vars(grepl( '^E10', .)))
>
> It is bad form not to put spaces around the <- assignment.
>
>
> On May 15, 2020 10:00:04 AM PDT, Ana Marija <sokovic.anamarija using gmail.com> wrote:
> >Hello,
> >
> >I have a data frame:
> >
> >> dim(tot)
> >[1] 502536   1093
> >
> >How would I extract from it all strings that start with E10?
> >
> >I know how to extract all rows that contain with E10
> >df0<-tot %>% filter_all(any_vars(. %in% c('E10')))
> >> dim(df0)
> >[1] 5105 1093
> >
> >but I just need a vector of strings that start with E10...
> >it would look something like this:
> >
> >[1] "E102" "E109" "E108" "E103" "E104" "E105" "E101" "E106" "E107"
> >
> >Thanks
> >Ana
> >
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