Add a `df.to_string(max_number_of_visible_rows)` function about polars HOT 6 CLOSED

df.head(20).to_string()

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Or even just df[:20].to_string() :)

@DeflateAwning: can already achieve this cleanly - doesn't really seem to be any need (or subsequent advantage) for moving the "head" (or "slice") call inside to_string. I don't think we do that anywhere else, so makes sense to keep things consistent/composable here 🤔

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Hmm I'm not sure we're talking about the same thing.

In Python:

In [1]: df = pl.DataFrame([{'id': i} for i in range(30)])

In [2]: df
Out[2]: 
shape: (30, 1)
┌─────┐
│ id  │
│ --- │
│ i64 │
╞═════╡
│ 0   │
│ 1   │
│ 2   │
│ 3   │
│ 4   │
│ …   │
│ 25  │
│ 26  │
│ 27  │
│ 28  │
│ 29  │
└─────┘

# Snly 10 rows are visible. I want all 20 rows to be visible.
print(str(df.head(20)))
shape: (20, 1)
┌─────┐
│ id  │
│ --- │
│ i64 │
╞═════╡
│ 0   │
│ 1   │
│ 2   │
│ 3   │
│ 4   │
│ …   │
│ 15  │
│ 16  │
│ 17  │
│ 18  │
│ 19  │
└─────┘

In Rust, I assume the same thing happens.

I see now that the config page has this example:

with pl.Config(tbl_rows=2):
    print(df)

This is what I was looking for in Python.

In Rust however, I don't see an equivalent set_tbl_rows: search. Any advice?

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It looks like it sets an env variable:

Which I guess is done with std::env in Rust?

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This seems like a bizarre way to communicate what, in my opinion, should be a simple argument.

Imagine if .dt.strftime(...) communicated the date format via an environment variable.

from polars.

It's very possible I'm missing something here - this was just what I found when trying to figure out how it currently works in py-polars

I'm guessing that eventually the Rust API will have a pl.Config equivalent?

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