(gallery_add_reference_bands)=

# Add Reference Bands

Draw reference bands to highlight specific regions.



::::::{tab-set}
:class: full-width
:sync-group: backend

:::::{tab-item} Matplotlib
:sync: matplotlib

![Matplotlib version of add_reference_bands](_images/add_reference_bands.png)

:::::

:::::{tab-item} Bokeh
:sync: bokeh

```{bokeh-plot}
:source-position: none

from bokeh.plotting import show

from arviz_base import load_arviz_data

import arviz_plots as azp

azp.style.use("arviz-variat")

data = load_arviz_data("centered_eight")
rope = [(-1, 1)]
pc = azp.plot_forest(
data,
backend="bokeh",   # change to preferred backend
)
pc.coords = {"column": "forest"}
pc = azp.add_bands(
pc,
values=rope,
visuals={"ref_band":{"color": "C1"}},
)



# for some reason the bokeh plot extension needs explicit use of show
show(pc.viz["figure"].item() if pc.viz["figure"].item() is not None else pc.viz["plot"].item())
```

Link to this page with the [bokeh tab selected](https://arviz-plots.readthedocs.io/en/latest//gallery/add_reference_bands.html?backend=bokeh#synchronised-tabs)
:::::

:::::{tab-item} Plotly
:sync: plotly

```{jupyter-execute}
:hide-code:

from arviz_base import load_arviz_data

import arviz_plots as azp

azp.style.use("arviz-variat")

data = load_arviz_data("centered_eight")
rope = [(-1, 1)]
pc = azp.plot_forest(
data,
backend="plotly",   # change to preferred backend
)
pc.coords = {"column": "forest"}
pc = azp.add_bands(
pc,
values=rope,
visuals={"ref_band":{"color": "C1"}},
)

pc.show()
```

Link to this page with the [plotly tab selected](https://arviz-plots.readthedocs.io/en/latest//gallery/add_reference_bands.html?backend=plotly#synchronised-tabs)
:::::
::::::

```{literalinclude} _scripts/add_reference_bands.py
:emphasize-lines: 11
```



:::{seealso}
API Documentation: {func}`~arviz_plots.add_bands`
:::



## Other examples with `plot_forest`

```{eval-rst}
.. minigallery:: plot_forest
```


:::{div} example-plot-download
{download}`Download Python Source Code: add_reference_bands.py<_scripts/add_reference_bands.py>`
:::