“Keep-header” is a command-line utility designed to preserve the first line (header) of a file while applying various operations or transformations to the remaining lines of the file. This tool is particularly useful when working with structured data files, such as CSV (comma-separated values) or TSV (tab-separated values) files, where the first line typically contains column headers.
Here’s an elaboration on the key features and functionality of “keep-header”:
- Preservation of Header: The primary function of “keep-header” is to ensure that the header line of a file remains unchanged and is passed directly to the standard output (stdout) without any modifications. This ensures that the column headers remain intact and are not affected by subsequent operations.
- Data Manipulation: While the header line remains untouched, “keep-header” allows users to apply various commands or operations to the data lines (rows) of the file. These operations can include filtering, sorting, aggregating, joining, or any other data manipulation tasks supported by the utility being used in conjunction with “keep-header.”
- Structured Data Files: “Keep-header” is commonly used in conjunction with utilities or scripts that process structured data files, such as TSV-utils, CSVKit, or similar tools. These utilities often provide a range of functionalities for working with structured data, and “keep-header” ensures that the column headers are preserved while the data is being manipulated.
- Command-Line Interface: “Keep-header” is typically invoked from the command line, where users specify the input file containing the data to be processed and the desired operations to be performed. The tool processes the input file, preserves the header line, applies the specified operations to the data lines, and outputs the result to the standard output.
- Use Cases: Common use cases for “keep-header” include data cleaning, data transformation, data analysis, and data integration tasks where preserving the integrity of the column headers is essential. By keeping the header line intact, users can ensure that the resulting data remains structured and well-defined, facilitating downstream processing and analysis.
- Documentation and Resources: “Keep-header” is typically part of a larger toolkit or library designed for working with structured data files. Users can refer to the documentation and resources provided by the respective toolkit or library for detailed usage instructions, examples, and best practices for incorporating “keep-header” into their data processing workflows.
keep-header Command Examples
1. Sort a file and keep the first line at the top:
# keep-header [path/to/file] -- sort
2. Output first line directly to stdout, passing the remainder of the file through the specified command:
# keep-header [path/to/file] -- [command]
3. Read from stdin, sorting all except the first line:
# cat [path/to/file] | keep-header -- [command]
4. Grep a file, keeping the first line regardless of the search pattern:
# keep-header [path/to/file] -- grep [pattern]
Summary
Overall, “keep-header” serves as a valuable tool for maintaining the integrity of column headers in structured data files while performing various data manipulation and processing tasks. By preserving the header line, users can ensure consistency and accuracy in their data processing workflows, ultimately leading to more reliable and actionable insights from the data.