Save data frame to a CSV file or to a `TextWriter`. When calling the operation, you can specify whether you want to save the row keys or not (and headers for the keys) and you can also specify the separator (use `\t` for writing TSV files). When specifying file name ending with `.tsv`, the `\t` separator is used automatically. ## Parameters - `path` - Specifies the output file name where the CSV data should be written - `keyNames` - Specifies the CSV headers for row key (or keys, for multi-level index) - `separator` - Specify the column separator in the file (the default is `\t` for TSV files and `,` for CSV files) - `culture` - Specify the `CultureInfo` object used for formatting numerical data [category:Input and output]

public static void SaveCsv<TRowKey, TColumnKey>(
	Frame<TRowKey, TColumnKey> frame,
	string path,
	IEnumerable<string> keyNames
)