Julian

Constrained Optimization (especially lower+upper bounds)

5

Hello, Coming from Python (`scipy.optimize.minimize`) and MATLAB (`fmincon`), I can't find a way to specify bounds (and other constraints), which to me are very essential parts of real world application...

Constrained Optimization (especially lower+upper bounds)

6

Hello, Coming from Python (`scipy.optimize.minimize`) and MATLAB (`fmincon`), I can't find a way to specify bounds (and other constraints), which to me are very essential parts of an optimization problem....

DataFrame & Series html repr in notebook (`_repr_html`)

2

### Problem description In my opinion output of notebook cells should be clear, brief and concise to keep a good overview and be able to compare the output of different...

### Polars version 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...

Multiple Condition Mapping like `numpy.select`

9

### Problem description #5822 would be really great for mapping column values with a descrete/fixed set of possible values. But additionally there are many cases where it is impossible to...

Map DataFrame Column using Python Dicts

3

### Problem description similar to here (#5815) but much more general it would be great if you could map column values of any type to any type with simple python...

Unique / Duplicate Enhancements

5

### Problem description this is an extension to #5590 with some examples and explanations. # Problems / Issues 1. `unique`: There is no way to remove ALL duplicates like in...

`update` DataFrame rows based on other DataFrame

3

### Problem description afaik, there currently is no way to update rows in a DataFrame based on another DataFrame My current workaround looks like this: ```python import polars as pl...

Add `values_counts` to DataFrame (+ `Expr.normalize`)

2

### Problem description `Expr.value_counts` and `Series.value_counts` are already supported. Is there a reason why this is not supported on a DataFrame? (Is this to reduce the API surface?) ```python import...

### Problem description @ritchie46 (as discussed I created a separate issue) There is no fast / elegant way to get boolean mask of a column containing lists with duplicates. `has_duplicates`...