How to drop data frame columns by name

Question

This is a sample data frame:

df1<-as.data.frame(matrix(sample(c( 1:10), 100, replace = TRUE), 10))
> df1
   V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
1  10  6  6  2  1  7  5  9  6   1
2   3  6 10  2  9  8  5  8  8   4
3  10  6  6 10  5  7  3  3 10   1
4   8  5  1 10  1 10  9 10  3   4
5   8  8  7  6  2  3  2 10  6   5
6   9  3  3  6  8  1  3  8  7  10
7   5  5  8 10 10  2  5  6  9   3
8   7  9  1  9  7  7  4  8  1   9
9   9 10 10  5  5  6 10  1  8   5
10  6 10  5  7  5  6  6  3  8  10

I want to remove v2 and v4 columns, but how?

Thanks in Advance!!

Answer 1

Easily you can do it:

drops <- c("V2","V4")
df1[ , !(names(df1) %in% drops)]

df1[ , !(names(df1) %in% drops)]
   V1 V3 V5 V6 V7 V8 V9 V10
1  10  6  1  7  5  9  6   1
2   3 10  9  8  5  8  8   4
3  10  6  5  7  3  3 10   1
4   8  1  1 10  9 10  3   4
5   8  7  2  3  2 10  6   5
6   9  3  8  1  3  8  7  10
7   5  8 10  2  5  6  9   3
8   7  1  7  7  4  8  1   9
9   9 10  5  6 10  1  8   5
10  6  5  5  6  6  3  8  10