# Description
Provides the ability to decomes struct columns into seperate columns for
each field:
<img width="655" alt="Screenshot 2024-10-16 at 09 57 22"
src="https://github.com/user-attachments/assets/6706bd36-8d38-4365-b58d-ba82f2d5ba9a">
# User-Facing Changes
- provides a new command `polars unnest` for decomposing struct fields
into separate columns.
# Description
This fixes an issue with converting to a dataframe when specifying a
struct in the schema. Things like the following now work correctly:
```nushell
[[foo bar]; [{a: "a_0", b:"b_0"} 1] [{a: "a_1", b: "b_1" } 2]] | polars into-df -s {foo: {a: str, b: str}, bar: u8}
```
# Description
Introduces a new flag `--truncate-ragged-lines` for `polars open` that
will truncate lines that are longer than the schema.
# User-Facing Changes
- Introduction of the flag `--truncate-ragged-lines` for `polars open`
# Description
This request exposes the prelude::polars::len expression. It is ended
for doing fast select count(*) like operations:
<img width="626" alt="Screenshot 2024-09-26 at 18 14 45"
src="https://github.com/user-attachments/assets/74285fc6-f99c-46e0-9226-9a7d41738d78">
# User-Facing Changes
- Introduction of the `polars len` command
# Description
Fixes: #12726 and #13185
Previously converting columns that contained null caused polars to force
a dtype of object even when using a schema.
Now:
1. When using a schema, the type the schema defines for the column will
always be used.
2. When a schema is not used, the previous type is used when a value is
null.
# User-Facing Changes
- The type defined by the schema we be respected when passing in a null
value `[a]; [null] | polars into-df -s {a: str}` will create a df with
an str dtype column with one null value versus a column of type object.
- *BREAKING CHANGE* If you define a schema, all columns must be in the
schema.
# Description
In order to be more consistent with it's nu counterpart, `polars save`
now returns an empty pipeline instead of a message of the saved file.
# User-Facing Changes
- `polars save` no longer displays a save message, making it consistent
with `save` behavior.
# Description
This PR:
- Removes the lazy_command, expr_command macros and migrates the
commands that were utilizing them.
- Removes the custom logic in DataFrameValues::is_equals to use the
polars DataFrame version of PartialEq
- Adds examples to commands that previously did not have examples or had
inadequate ones.
NOTE: A lot of examples now have a `polars sort` at the end. This is
needed due to the comparison in the result. The new polars version of
equals cares about the ordering. I removed the custom equals logic as it
causes comparisons to lock up when comparing dataframes that contain a
row that contains a list. I discovered this issue when adding examples
to `polars implode`
# Description
Previously there were no examples or explanations that you can use '*'
to select all columns. Updated description and added a new example.
