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rdplyrfilteringr-rownames

Get row names based on column values, R, multiple conditions

Using the sample data set mtcars

head(mtcars)
                   mpg cyl disp  hp drat    wt  qsec vs am gear carb
Mazda RX4         21.0   6  160 110 3.90 2.620 16.46  0  1    4    4
Mazda RX4 Wag     21.0   6  160 110 3.90 2.875 17.02  0  1    4    4
Datsun 710        22.8   4  108  93 3.85 2.320 18.61  1  1    4    1
Hornet 4 Drive    21.4   6  258 110 3.08 3.215 19.44  1  0    3    1
Hornet Sportabout 18.7   8  360 175 3.15 3.440 17.02  0  0    3    2
Valiant           18.1   6  225 105 2.76 3.460 20.22  1  0    3    1

I want to get the rownames into a vection in all cases where the cyl==4|cyl==6

I found the code

rowname_vec<-which(mtcars[mtcars$cyl==4,])

But I do not know how to make this work with multiple conditions. (getting the row names for 4 a 6 cyl cars)

Solution

  • Using %in%

    row.names(mtcars)[with(mtcars, cyl %in% c(4, 6))]