You can use the following methods to only keep certain columns in a data frame in R:

Method 1: Specify Columns to Keep

#only keep columns 'col1' and 'col2'
new_df = subset(df, select = c(col1, col2))

Method 2: Specify Columns to Drop

#drop columns 'col3' and 'col4'
new_df = subset(df, select = c(col3, col4))

The following examples show how to use each method with the following data frame in R:

#create data frame
df <- data.frame(team=c('A', 'A', 'A', 'B', 'B', 'B'),
                 points=c(19, 14, 14, 29, 25, 30),
                 assists=c(4, 5, 5, 4, 12, 10),
                 rebounds=c(9, 7, 7, 6, 10, 11))

#view data frame
df

  team points assists rebounds
1    A     19       4        9
2    A     14       5        7
3    A     14       5        7
4    B     29       4        6
5    B     25      12       10
6    B     30      10       11

Method 1: Specify Columns to Keep

The following code shows how to define a new data frame that only keeps the “team” and “assists” columns:

#keep 'team' and 'assists' columns
new_df = subset(df, select = c(team, assists))

#view new data frame
new_df

  team assists
1    A       4
2    A       5
3    A       5
4    B       4
5    B      12
6    B      10

The resulting data frame only keeps the two columns that we specified.

Method 2: Specify Columns to Drop

The following code shows how to define a new data frame that drops the “team” and “assists” columns from the original data frame:

#drop 'team' and 'assists' columns
new_df = subset(df, select = -c(team, assists))

#view new data frame
new_df

  points rebounds
1     19        9
2     14        7
3     14        7
4     29        6
5     25       10
6     30       11

The resulting data frame drops the “team” and “assists” columns from the original data frame and keeps the remaining columns.