algebraixlib.io.csv module

Import regular clans from and export them to CSV data.

algebraixlib.io.csv.export_csv(absolute_clan: 'PP(A x A)', file_or_path, ordered_lefts=None, sort_key=None)[source]

Export a regular, absolute clan as CSV file with header row.

The left components of the clan are interpreted as column names and are exported as header row. Every relation in the clan becomes a data row in the CSV file.

Parameters:
  • absolute_clan – A regular, absolute clan.
  • file_or_path – Either a file path (in this case the CSV data is written to a file at this location) or a file object (in this case the CSV data is written to its .write() function).
  • ordered_lefts – (Optional) A Sequence of lefts that are exported in the given order. Default is the sequence that is the lexically sorted left set of the clan.
  • sort_key – (Optional) A function that compares two row-relations and provides an order (for use with sorted()). The output is not sorted if sort_key is missing.
Returns:

True if the CSV export succeeded, Undef() if not.
algebraixlib.io.csv.import_csv(csv_file_or_filepath, types=None, skip_rows=0, index_column=None, has_dup_rows=False) → 'PP( A x M )'[source]

Import the file csv_file_or_filepath as CSV data and return a clan.

Parameters:
  • csv_file_or_filepath – The file path or file object (for example StringIO buffer) to import.
  • types – (Optional) A dictionary of type conversions. The keys are the column names; the values are functors (or types) that receive the string from the CSV cell and return the value to be imported. Example: {'foo': int, 'bar': float}. By default all values are interpreted as strings.
  • skip_rows – (Optional) A number of lines to skip (default 0). Some CSV files have a preamble that can be skipped with this option.
  • index_column – (Optional) A name for an index column. (No index column is created if this argument is not specified.) The index starts with 0. (This option is not compatible with the has_dup_rows option.)
  • has_dup_rows – (Optional) If True, allow duplicate rows and return a multiclan instead of a clan. By default, the value is False and a clan is returned. (This option is not compatible with the option index_column.)
Returns:

A clan (if has_dup_rows is ``False or not provided) or a multiclan (if has_dup_rows is True).