changing dtypes in tibble

[kgilpas]

Is there a way to change the dtypes seen in a tibble? say changing from f64 to i64?

[markfairbanks]

Yep - much like in R the best way to do this is inside a .mutate().

You can use as_boolean(), as_float(), as_string(), as_integer() or you can use a more general cast() function that gives you access to all polars types.

All of these can be found in the function reference here

import tidypolars as tp
from tidypolars import col

df = tp.Tibble(int_col = range(3), float_col = [1.0, 2.0, 3.0])

(
    df
    .mutate(as_boolean = tp.as_boolean('int_col'),
            as_integer = tp.as_integer('float_col'),
            cast = tp.cast('int_col', tp.Float64))
)

shape: (3, 5)
┌─────────┬───────────┬────────────┬────────────┬──────┐
│ int_col ┆ float_col ┆ as_boolean ┆ as_integer ┆ cast │
│ ---     ┆ ---       ┆ ---        ┆ ---        ┆ ---  │
│ i64     ┆ f64       ┆ bool       ┆ i64        ┆ f64  │
╞═════════╪═══════════╪════════════╪════════════╪══════╡
│ 0       ┆ 1.0       ┆ false      ┆ 1          ┆ 0.0  │
├╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌┤
│ 1       ┆ 2.0       ┆ true       ┆ 2          ┆ 1.0  │
├╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌┤
│ 2       ┆ 3.0       ┆ true       ┆ 3          ┆ 2.0  │
└─────────┴───────────┴────────────┴────────────┴──────┘

Hope this helps - if you have any questions let me know.