## from_column
Specify that a style value should be fetched from a column in the data.
Usage
``` python
from_column(
column,
na_value=None,
fn=None,
)
```
## Parameters
`column: str`
A column name in the data containing the styling information.
`na_value: Any | None = None`
A single value to replace any NA values in the column (currently not supported).
`fn: Callable[[Any], Any] | None = None`
A callable applied to transform each value extracted from `column=`.
## Examples
This example demonstrates styling the `"x"` column.
Style the text color using the `"color"` column:
``` python
import pandas as pd
import polars as pl
from great_tables import GT, from_column, loc, style, px
df = pd.DataFrame({"x": [15, 20], "color": ["red", "blue"]})
(GT(df).tab_style(style=style.text(color=from_column("color")), locations=loc.body(columns=["x"])))
```
| x | color |
|-----|-------|
| 15 | red |
| 20 | blue |
With polars, you can pass expressions directly:
``` python
df_polars = pl.from_pandas(df)
(
GT(df_polars).tab_style(
style=style.text(color=pl.col("color")), locations=loc.body(columns=["x"])
)
)
```
| x | color |
|-----|-------|
| 15 | red |
| 20 | blue |
Style the text size using values from the `"x"` column, with the `px()` helper function as the `fn=` parameter:
``` python
(
GT(df).tab_style(
style=style.text(color=from_column("color"), size=from_column("x", fn=px)),
locations=loc.body(columns=["x"]),
)
)
```
| x | color |
|-----|-------|
| 15 | red |
| 20 | blue |