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Trouble with Polars input

2 posts from 2 people2d activeSteady, +1 this weekunverified

Posts per day

Posts per day2 posts, Sep 3 to Nov 13

The posts behind it

GitHub issuespola-rs/polars · FBruzzesiNov 7

Plugin built with `#[polars_expr(output_type=...)]` aborts the process on an input dtype its polars build lacks

...265 of 293 `#[polars_expr]` uses). As far as I could tell, from the plugin side there is no way to guard this, since the panic happens before any user code runs. > [!NOTE] > The current workaround is to enable every dtype feature on the plugin's `polars` dependency...

GitHub issuespola-rs/polars · AidavdwOct 5

`diff(n, null_behavior="drop")` panics when the input is shorter than `n`

### Checks - [x] I have checked that this issue has not already been reported. - [x] I have confirmed this bug exists on the [latest version](https://pypi.org/project/polars/) of Polars. ### Reproducible example The bug does not only show up with lists directly either: ### Log...

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Companies and products named

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About this problem

Evidence

2 posts from 2 people in 1 place, about 1 a week over 34 days. Mostly on pola-rs/polars. Tools named alongside: PyPI.

Frustration Frustration 0 of 3· Seen on GitHub issues

How it was grouped

Posts about Polars with no known issue, sharing the word "input". First post Oct 5, 2026, latest Nov 7, 2026. Unverified: fewer than 3 posts, or one person or place only. Method

Other Polars problems

Trouble with Polars group

Top post: "Datetime out-of-range in `group_by_dynamic` streaming engine", one of 10 posts from 7 people on GitHub issues.

Trouble with Polars join

Top post: "Coalescing full join on Int32-vs-Int64 keys with `unique` incorrect", one of 8 posts from 8 people on GitHub issues.

Polars upgrades break working setups

24 posts from 17 people on GitHub issues.

Trouble with Polars column

Top post: "Compare lists in one column to the first n elements of another column in Python Polars lazyframes, where n is", one of 21 posts from 16 people on GitHub issues, Stack Overflow.

Polars users keep filing bugs

Top post: "Consider upgrading the brotli crate (CVE-2026-111497)", one of 20 posts from 14 people on GitHub issues.

Trouble with Polars parquet

Top post: "`is_in` with more than 100 values does not skip Parquet row groups between the values", one of 7 posts from 7 people on GitHub issues.

Trouble with Polars cache

Top post: "Predicate pushdown into a shared cache applies a filter below each branch's slice", one of 5 posts from 4 people on GitHub issues.

Trouble with Polars streaming

Top post: "`min_by`/`max_by`/`sort_by` with a scalar `by`: in-memory engine raises, streaming broadcasts", one of 5 posts from 3 people on GitHub issues.

Trouble with Polars instead

Top post: "Series.to_list() panics on out-of-range datetimes instead of raising an error", one of 5 posts from 5 people on GitHub issues.

Trouble with Polars iceberg

Top post: "`sink_iceberg` ignores catalog credentials", one of 5 posts from 3 people on GitHub issues.

Bad data slips through Polars unnoticed

4 posts from 4 people on GitHub issues, Reddit.

Trouble with Polars value

Top post: "polars.read_excel() value error on very large date", one of 4 posts from 4 people on GitHub issues.

History

Momentum went from fading to steady.

Nov 12, 2026

Momentum went from steady to fading.

Oct 12, 2026

Momentum went from fading to steady.

Oct 7, 2026

First seen with 1 post; the top post now: "`diff(n, null_behavior=drop)` panics when the input is shorter than `n`".

Sep 25, 2026