toCsv method
A conversion of this data frame to a csv representation.
Implementation
String toCsv({
String separator = ",",
Iterable<String>? columns,
Map<String, int> fixedPlaces = const {},
}) {
columns = columns ?? [...numericColumns.keys, ...categoricColumns.keys];
if (columns.any((column) =>
!numericColumns.containsKey(column) &&
!categoricColumns.containsKey(column))) {
throw PackhorseError.badArgument("Bad column name in $columns.");
}
final table = toListOfMaps(fixedPlaces: fixedPlaces),
sb = StringBuffer()..writeln(columns.join(separator));
for (final row in table) {
sb.writeln(columns.map((c) => row[c]!).join(","));
}
return sb.toString();
}