  Reusing and making sense of other scientists' computational notebooks.
However, making sense of existing notebooks is a struggle, as these reference
notebooks are often exploratory, have messy structures, include multiple
alternatives, and have little explanation. To help mitigate these issues, we
developed a catalog of cognitive tasks associated with the sensemaking process.
Utilizing this catalog, we introduce Porpoise: an interactive overlay on
computational notebooks. Porpoise integrates computational notebook features
with digital design, grouping cells into labeled sections that can be expanded,
collapsed, or annotated for improved sensemaking.
  We investigated data scientists' needs with unfamiliar computational
notebooks and investigated the impact of Porpoise adaptations on their
comprehension process. Our counterbalanced study with 24 data scientists found
Porpoise enhanced code comprehension, making the experience more akin to
reading a book, with one participant describing it as It's really like reading
a book.
