What does the -k3nr option in the sort command do?

The -k3nr option in the sort command is used to specify that the sorting should be based on the third field and that the sorting should be done numerically in reverse order.

Breakdown of the Option:

• -k3: This indicates that the sort should consider the third field (column) of the input data.
• n: This specifies that the sort should be done in numerical order.
• r: This indicates that the sort should be in reverse order (i.e., from highest to lowest).

Example:

Suppose you have a file named data.txt with the following content:

apple 10 5
banana 2 20
cherry 5 15

You can sort this data based on the third field (the numbers) in reverse numerical order using the -k3nr option as follows:

sort -k3nr data.txt

Output:

banana 2 20
cherry 5 15
apple 10 5

Explanation:

In this example, the lines are sorted based on the numerical values in the third field, resulting in the highest number appearing first. The r option ensures that the sorting is done in descending order.