bash Overview

grep

The grep utility is used for searching for regular expressions in files. There are many variants of the grep command.

Examples

Use the `grep` command to extract all of the lines from this file (`/anvil/projects/tdm/data/icecream/combined/reviews.csv`) that contain the word terrific and store these reviews in a new file called `terrificreviews.csv` in your home directory.

Click to see solution

%%bash
grep "terrific" /anvil/projects/tdm/data/icecream/combined/reviews.csv > $HOME/terrificreviews.csv

cut

We can use cut to extract information from a text file. We usually just need to specify the delimited between the fields of data, using the -d option, and we also need to specify the fields to extract, using the -f option. For example, we can display the city and state of the donations to federal election campaigns.

Examples

From the file `terrificreviews.csv` that you created in the previous example, how many of the reviews had only 1 star? How many had 4 stars? How many had 5 stars?

Click to see solution

%%bash
cut -d, -f5 $HOME/terrificreviews.csv | sort | uniq -c | sort -n

      1 1
      2 4
      9 5

There are nine 5-star reviews, 2 4-star reviews, and one 1-star review.