How to use the command xsv (with examples)

xsv is a CSV command-line toolkit written in Rust. It provides various useful commands for manipulating CSV files, such as inspecting headers, counting entries, selecting columns, and more.

Use case 1: Inspect the headers of a file

Code:

xsv headers path/to/file.csv

Motivation: When working with a new CSV file, it is important to know the names of the columns. The xsv headers command allows you to quickly view the headers of a CSV file.

Explanation: The command xsv headers takes the path to a CSV file as an argument, and it outputs the headers of that file.

Example output:

column_a,column_b,column_c

Use case 2: Count the number of entries

Code:

xsv count path/to/file.csv

Motivation: Sometimes you need to know how many entries there are in a CSV file. The xsv count command provides a simple way to count the number of entries in a CSV file.

Explanation: The command xsv count takes the path to a CSV file as an argument, and it outputs the number of entries in that file.

Example output:

1000

Use case 3: Get an overview of the shape of entries

Code:

xsv stats path/to/file.csv | xsv table

Motivation: Understanding the general structure and statistics of a CSV file can be helpful for data analysis. The xsv stats command provides an overview of the shape of entries in a CSV file, and the xsv table command formats the output in a tabular format for easier readability.

Explanation: The xsv stats command takes the path to a CSV file as an argument and generates statistical information about the file. The xsv table command is used to format the output into a tabular format.

Example output:

field      type    min       max       sum       mean      median    stdev
column_a   integer  1         100       5050      50.50     50.50     29.01
column_b   float    1.23      99.99     5077.55   50.78     50.78     29.01

Use case 4: Select a few columns

Code:

xsv select column_a,column_b path/to/file.csv

Motivation: Sometimes you may only need to work with specific columns in a CSV file. The xsv select command allows you to select and extract the desired columns from a CSV file.

Explanation: The command xsv select takes a comma-separated list of column names as an argument and the path to a CSV file. It outputs the selected columns from the file.

Example output:

column_a,column_b
1,1.23
2,4.56
3,7.89
...

Use case 5: Show 10 random entries

Code:

xsv sample 10 path/to/file.csv

Motivation: Randomly sampling entries from a CSV file can be useful for data exploration or testing purposes. The xsv sample command allows you to select a random sample from a CSV file.

Explanation: The command xsv sample takes the number of entries to sample as an argument and the path to a CSV file. It outputs a random sample of the specified number of entries from the file.

Example output:

column_a,column_b,column_c
65,4.31,foo
876,0.12,bar
443,8.52,baz
...

Use case 6: Join a column from one file to another

Code:

xsv join --no-case column_a path/to/file/a.csv column_b path/to/file/b.csv | xsv table

Motivation: Joining columns from multiple CSV files based on a common field can be useful for consolidating data or performing analysis on combined datasets. The xsv join command allows you to join columns from different CSV files.

Explanation: The xsv join command takes multiple arguments in the form column_a path/to/file/a.csv column_b path/to/file/b.csv. It joins the specified columns from the given files based on the common field. The --no-case flag is used to perform a case-insensitive join. The xsv table command formats the output into a tabular format.

Example output:

column_a,column_c,column_b
1,foo,apple
2,bar,banana
3,baz,orange
...

Conclusion:

The xsv command-line toolkit is a powerful tool for working with CSV files. It provides a range of useful commands for inspecting, manipulating, and analyzing CSV data. By using these commands, you can easily perform common tasks such as inspecting headers, counting entries, selecting columns, and more. Whether you are a data analyst, developer, or any professional dealing with CSV files, xsv can greatly simplify your workflow and make data manipulation tasks more efficient.