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DOC: Clarify interaction of read_csv nrows with other args (#59078) #59084

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DOC: Clarify interaction of read_csv nrows with other args (#59078) #59084

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DOC: Clarify interaction of read_csv nrows with other args (#59078)
mdavis-xyz Jun 24, 2024
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DOCS: Simplify explanation of read_csv nrows
mdavis-xyz Jun 26, 2024
8ebb3e1
Merge branch 'pandas-dev:main' into 59078-nrow-doc
mdavis-xyz Jun 27, 2024
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12 changes: 11 additions & 1 deletion pandas/io/parsers/readers.py
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Expand Up @@ -268,7 +268,17 @@ class _read_shared(TypedDict, Generic[HashableT], total=False):
skipfooter : int, default 0
Number of lines at bottom of file to skip (Unsupported with ``engine='c'``).
nrows : int, optional
Number of rows of file to read. Useful for reading pieces of large files.
Number of rows of data to read. Useful for reading pieces of large files.
The following rows are excluded from the count:

* The header row containing column names,
* Rows before the header row, if ``header=1`` or larger,
* Fully commented rows,
* Rows skipped with ``skiprows``,
* Skipped blank lines.
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The last 3 seem obvious to me, it might be better to remove them since the doc page of read_csv is quite long already.

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Should I just say that nrows limits the number of rows of the returned dataframe? I can't find any edge case where that is not true.

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Sounds good

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Ok I've updated that now.


Records containing text with newline characters within quotes
or escaped newline characters will be counted as one row.
na_values : Hashable, Iterable of Hashable or dict of {{Hashable : Iterable}}, optional
Additional strings to recognize as ``NA``/``NaN``. If ``dict`` passed, specific
per-column ``NA`` values. By default the following values are interpreted as
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