toCSVDirectory method

Future<void> toCSVDirectory(String dirPath)

Saves the DataCube to a directory of CSV files.

Each sheet (depth level) is saved as a separate CSV file. Files are named: sheet_0.csv, sheet_1.csv, etc.

Note: This method requires dart:io and is only available on non-web platforms.

Example:

var cube = DataCube.zeros(3, 4, 5);
await cube.toCSVDirectory('cube_data');
// Creates: cube_data/sheet_0.csv, cube_data/sheet_1.csv, cube_data/sheet_2.csv

Implementation

Future<void> toCSVDirectory(String dirPath) async {
  final fileIO = FileIO();

  // Create directory if needed (platform-specific)
  await _ensureDirectoryExists(dirPath);

  // Save metadata
  final metadata = {
    'type': 'DataCube',
    'version': '1.0',
    'depth': depth,
    'rows': rows,
    'columns': columns,
    'attributes': attrs.toJson(),
  };
  await fileIO.saveToFile('$dirPath/metadata.json', jsonEncode(metadata));

  // Save each sheet as CSV
  for (int d = 0; d < depth; d++) {
    final frame = getFrame(d);
    await fileIO.saveToFile('$dirPath/sheet_$d.csv', _dataFrameToCSV(frame));
  }
}