Sankey Chart

>>> from techminer2.co_occurrence_matrix import sankey_chart
>>> plot = sankey_chart(
...     #
...     # PARAMS:
...     fields=["authors", "countries", "author_keywords"],
...     max_n=20,
...     retain_counters=True,
...     #
...     # ITEM FILTERS:
...     top_n=10,
...     occ_range=None,
...     gc_range=None,
...     custom_terms=None,
...     #
...     # PARAMS:
...     font_size=8,
...     title=None,
...     color=None,
...     #
...     # DATABASE PARAMS:
...     root_dir="example/",
...     database="main",
...     year_filter=None,
...     cited_by_filter=None,
... )
>>> # plot.write_html("sphinx/_static/co_occurrence_matrix/sankey_chat.html")