fix typo
clean comment
implement stacked area chart
add message before failing when numpy is not installed
add message before failing when numpy is not installed
clean Bar code and rename value to values
clean BoxPlot code and rename value to values
fix case when DataAdapter.convert_items_to_dict is set to True improperly
clean HeatMap example
clean Donut code and example
clean Donut code (unused imports)
clean Dot chart code
clean Histogram code and example
clean Line code and example
clean Scatter code and example
clean TimeSeries code and example