New Features
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- Default plot canvas and its API is available now!
- Add side area and its interface to all the table widget.
- Find/replace widget (Ctrl+F).
- Evaluate widget (in toolbar).
- Filter widget (in toolbar).
- Add preview widgets to many of the dialogs that return DataFrame or update plots.
- Format all the undoable operations in a semi-executable fashion.
- Add undo stack view.
Improvements
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- Customize QSplitter's handles to make it easier to grab.
- Override event filters to make console shortcuts better.
- Reset selection on insertion or removal of rows or columns.
- Make dock widget title bars better.
- `cell` interface accept array and out-of-bound slicing.
Changes
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- NaN is replaced to `""` in spreadsheet instead of `np.nan`.
- Some keymaps are changed because they did not work in some keyboards.
Bug Fixes
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- DataFrame was not copied correctly in some occasions.
- `bind_key` was not compatible with some functions.
- Table tiling and non-standard view mode had many problems in the GUI.
- Many focusing bugs were fixed.
- Do not synchronize zoom factor between tables created from the same data model.
- Ctrl+Shift+Arrow did not work as expected.
- Inserting/removing rows or columns in GUI was not undoable.
- Editing headers emitted wrong signals.