Parse a comma-separated list of column indices AND/OR names into a list of integer indices. Ranges of integers can be specified with two integers separated by a '-' or ':' character. Ranges of non-integers (e.g. column names) are not supported. Note: Column indices are 1-based.
(ids, column_names, column_offset=1, excluded_columns=None)
| 513 | |
| 514 | |
| 515 | def parse_column_identifiers(ids, column_names, column_offset=1, excluded_columns=None): |
| 516 | """ |
| 517 | Parse a comma-separated list of column indices AND/OR names into a list of integer indices. |
| 518 | Ranges of integers can be specified with two integers separated by a '-' or ':' character. |
| 519 | Ranges of non-integers (e.g. column names) are not supported. |
| 520 | Note: Column indices are 1-based. |
| 521 | """ |
| 522 | if not column_names: |
| 523 | return [] |
| 524 | |
| 525 | if not ids and not excluded_columns: |
| 526 | return range(len(column_names)) |
| 527 | |
| 528 | if ids: |
| 529 | columns = [] |
| 530 | |
| 531 | for c in ids.split(','): |
| 532 | try: |
| 533 | columns.append(match_column_identifier(column_names, c, column_offset)) |
| 534 | except ColumnIdentifierError: |
| 535 | if ':' in c: |
| 536 | a, b = c.split(':', 1) |
| 537 | elif '-' in c: |
| 538 | a, b = c.split('-', 1) |
| 539 | else: |
| 540 | raise |
| 541 | |
| 542 | try: |
| 543 | a = int(a) if a else 1 |
| 544 | b = int(b) + 1 if b else len(column_names) + 1 |
| 545 | except ValueError: |
| 546 | raise ColumnIdentifierError( |
| 547 | "Invalid range %s. Ranges must be two integers separated by a - or : character.") |
| 548 | |
| 549 | for x in range(a, b): |
| 550 | columns.append(match_column_identifier(column_names, x, column_offset)) |
| 551 | else: |
| 552 | columns = range(len(column_names)) |
| 553 | |
| 554 | excludes = [] |
| 555 | |
| 556 | if excluded_columns: |
| 557 | for c in excluded_columns.split(','): |
| 558 | try: |
| 559 | excludes.append(match_column_identifier(column_names, c, column_offset)) |
| 560 | except ColumnIdentifierError: |
| 561 | if ':' in c: |
| 562 | a, b = c.split(':', 1) |
| 563 | elif '-' in c: |
| 564 | a, b = c.split('-', 1) |
| 565 | else: |
| 566 | # Ignore unknown columns. |
| 567 | continue |
| 568 | |
| 569 | try: |
| 570 | a = int(a) if a else 1 |
| 571 | b = int(b) + 1 if b else len(column_names) |
| 572 | except ValueError: |