3.1.0

New features

• Added several features to simplify interaction with DynamicTable objects that link to other tables via
  DynamicTableRegion columns. @oruebel (#645)
  • Added DynamicTable.get_foreign_columns to find all columns in a table that are a DynamicTableRegion
  • Added DynamicTable.has_foreign_columns to identify if a DynamicTable contains DynamicTableRegion columns
  • Added DynamicTable.get_linked_tables to retrieve all tables linked to either directly or indirectly from
    the current table via DynamicTableRegion
  • Implemented the new get_foreign_columns, has_foreign_columns, and get_linked_tables also for
    AlignedDynamicTable
  • Added new module hdmf.common.hierarchicaltable with helper functions to facilitate conversion of
    hierarchically nested DynamicTable objects via the following new functions:
    • to_hierarchical_dataframe to merge linked tables into a single consolidated pandas DataFrame.
    • drop_id_columns to remove "id" columns from a DataFrame.
    • flatten_column_index to replace a pandas.MultiIndex with a regular pandas.Index

Bug fixes

• Do not build wheels compatible with Python 2 because HDMF requires Python 3.7. @rly (#642)
• AlignedDynamicTable did not overwrite its get function. When using DynamicTableRegion to referenece AlignedDynamicTable this led to cases where the columns of the category subtables where omitted during data access (e.g., conversion to pandas.DataFrame). This fix adds the AlignedDynamicTable.get based on the existing AlignedDynamicTable.__getitem__. @oruebel (#645)
• Fixed #651 to support selection of cells in an AlignedDynamicTable via slicing with [int, (str, str)](and [int, str, str]) to select a single cell, and [int, str] to select a single row of a category table. @oruebel (#645)

Minor improvements

• Updated DynamicTable.to_dataframe() and DynamicTable.get functions to set the .name attribute
  on generated pandas DataFrame objects. @oruebel (#645)
• Added AlignedDynamicTable.get_colnames(...) to support look-up of the full list of columns as the
  AlignedDynamicTable.colnames property only includes the columns of the main table for compliance with
  DynamicTable @oruebel (#645)
• Fix documentation for DynamicTable.get and DynamicTableRegion.get. @rly (#650)
• Allow passing string column name to DynamicTableRegion, i.e., dtr['col_name'] is a shortcut to
  dtr.table['col_name']. @rly (#657)