DOC: add sections about big new features (CoW, string dtype) to 3.0.0 whatsnew notes #61724
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This was referenced Jul 1, 2025
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mroeschke
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Jul 15, 2025
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| Starting with pandas 3.0, a dedicated string data type is enabled by default | ||
| (backed by PyArrow under the hood, if installed, otherwise falling back to | ||
| NumPy). This means that pandas will start inferring columns containing string |
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| NumPy). This means that pandas will start inferring columns containing string | |
| ``object``-dtype backed by NumPy). This means that pandas will start inferring columns containing string |
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With that edit it seems to suggest that it falls back to "object" dtype (as we currently use)? But it still has a StringDtype, just using numpy instead of pyarrow under the hood. So it is "backed by NumPy object dtype under the hood", so something like:
Suggested change
| NumPy). This means that pandas will start inferring columns containing string | |
| being backed by NumPy ``object``-dtype). This means that pandas will start inferring columns containing string |
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Yup that edit is clearer. Just didn't want to make this ambiguous to suggest it could be the new NumPy string type (which it isnt)
mroeschke
reviewed
Jul 15, 2025
mroeschke
reviewed
Jul 15, 2025
| how pandas operates with respect to copies and views. A summary of the changes: | ||
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| 1. The result of *any* indexing operation (subsetting a DataFrame or Series in any way, | ||
| i.e. including accessing a DataFrame column as a Series) or any method returning a |
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| i.e. including accessing a DataFrame column as a Series) or any method returning a | |
| e.g. accessing a DataFrame column as a Series) or any method returning a |
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We don't actually yet list the bigger features (string dtype, CoW, no silent downcasting) in the 3.0.0 whatsnew page, so starting to do that here.
Already pushed a section about string dtype, will further add a section about CoW and the downcasting.