[r] Filter rows which contain a certain string

edit included the newer across() syntax

Here's another tidyverse solution, using filter(across()) or previously filter_at. The advantage is that you can easily extend to more than one column.

Below also a solution with filter_all in order to find the string in any column, using diamonds as example, looking for the string "V"

library(tidyverse)

String in only one column

# for only one column... extendable to more than one creating a column list in `across` or `vars`!
mtcars %>% 
  rownames_to_column("type") %>% 
  filter(across(type, ~ !grepl('Toyota|Mazda', .))) %>%
  head()
#>                type  mpg cyl  disp  hp drat    wt  qsec vs am gear carb
#> 1        Datsun 710 22.8   4 108.0  93 3.85 2.320 18.61  1  1    4    1
#> 2    Hornet 4 Drive 21.4   6 258.0 110 3.08 3.215 19.44  1  0    3    1
#> 3 Hornet Sportabout 18.7   8 360.0 175 3.15 3.440 17.02  0  0    3    2
#> 4           Valiant 18.1   6 225.0 105 2.76 3.460 20.22  1  0    3    1
#> 5        Duster 360 14.3   8 360.0 245 3.21 3.570 15.84  0  0    3    4
#> 6         Merc 240D 24.4   4 146.7  62 3.69 3.190 20.00  1  0    4    2

The now superseded syntax for the same would be:

mtcars %>% 
  rownames_to_column("type") %>% 
  filter_at(.vars= vars(type), all_vars(!grepl('Toyota|Mazda',.))) 

String in all columns:

# remove all rows where any column contains 'V'
diamonds %>%
  filter(across(everything(), ~ !grepl('V', .))) %>%
  head
#> # A tibble: 6 x 10
#>   carat cut     color clarity depth table price     x     y     z
#>   <dbl> <ord>   <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
#> 1  0.23 Ideal   E     SI2      61.5    55   326  3.95  3.98  2.43
#> 2  0.21 Premium E     SI1      59.8    61   326  3.89  3.84  2.31
#> 3  0.31 Good    J     SI2      63.3    58   335  4.34  4.35  2.75
#> 4  0.3  Good    J     SI1      64      55   339  4.25  4.28  2.73
#> 5  0.22 Premium F     SI1      60.4    61   342  3.88  3.84  2.33
#> 6  0.31 Ideal   J     SI2      62.2    54   344  4.35  4.37  2.71

The now superseded syntax for the same would be:

diamonds %>% 
  filter_all(all_vars(!grepl('V', .))) %>%
  head

I tried to find an across alternative for the following, but I didn't immediately come up with a good solution:

    #get all rows where any column contains 'V'
    diamonds %>%
    filter_all(any_vars(grepl('V',.))) %>%
      head
    #> # A tibble: 6 x 10
    #>   carat cut       color clarity depth table price     x     y     z
    #>   <dbl> <ord>     <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
    #> 1 0.23  Good      E     VS1      56.9    65   327  4.05  4.07  2.31
    #> 2 0.290 Premium   I     VS2      62.4    58   334  4.2   4.23  2.63
    #> 3 0.24  Very Good J     VVS2     62.8    57   336  3.94  3.96  2.48
    #> 4 0.24  Very Good I     VVS1     62.3    57   336  3.95  3.98  2.47
    #> 5 0.26  Very Good H     SI1      61.9    55   337  4.07  4.11  2.53
    #> 6 0.22  Fair      E     VS2      65.1    61   337  3.87  3.78  2.49

Update: Thanks to user Petr Kajzar in this answer, here also an approach for the above:

diamonds %>%
   filter(rowSums(across(everything(), ~grepl("V", .x))) > 0)