Table Clean

Table Cleaning

Tidy up a CSV table and write the result to a new file. The whole process revolves around the header: read the table in, check whether the header is well-formed, and if it is not, repair it one spot at a time and check again, until it is well-formed or the repair bound is reached; finally write the result to a new file.

S1 Read

Use read_csv to read the file that path points to. Take the first line as the header row (header_row) and the remaining lines as data rows (rows).

S2 Header check

Decide whether the current header_row is well-formed.

S2.1 Well-formedness criterion

A header is well-formed if and only if its fields are separated by commas, every field name is non-empty, and no field contains the placeholder mark Unnamed. A header with an empty field or with Unnamed is malformed.

S3 Repair

If the header is malformed, repair it with fix_header, then go back to S2 and check again. Each repair handles only one spot, so a header with many bad fields needs several rounds. The number of repairs (fix_count) must not exceed 3; if the header is still malformed when the bound is reached, stop repairing.

S4 Export

Once the header is well-formed, use export to write the result to output_path.

P1 Prohibition

Never overwrite the source file. The target path of export, output_path, must not equal the source file path path. Even if the result is correct, a run whose export target is the source file is judged as rejected.