Plotly Express does not play well with templates

Hi,

I noticed that Plotly Express is quite opinionated with some default values, which unfortunately do not play well with template’s defined values such as graph height or color scale.

For example, I would expect px.histogram(some_dataframe, template="seaborn") to use the seaborn color palette.

Is there any plans to pick up default values in the active template instead?

[nicolaskruchten]

@Batalex this is now released! You should be able to set pio.templates.default and plotly_express will grab the colors from there, and it also respects px.defaults.template as well as the template kwarg.

[nicolaskruchten]

It would be nice if there was a logical correspondence between the px template and a user-specified template, so any px default parameter set to None has a template fallback.

The px defaults are very few: color scale and sequence, symbol/dash sequences and dimensions. Everything else is use-specified. Among those, color scale&sequence and width/height are the only ones that are present in the template.

there are a lot of places [the template] can be specified

Actually “[the template]” is not what I meant, I meant the colors 😃 In a template, we have color scales and sequences in a few places in layout such as layout.colorway, layout.piecolorway, layout.sunburstcolorway, layout.colorscale.sequential, layout.colorscale.sequentialminus, layout.colorscale.diverging but also on a per-trace-type basis: a template can specify one colorscale for scatter and another for heatmaps, and it can also specify that the first scatter is one color and the second is another, at which point I think that scatter traces will end up alternating between the two colors. So… yeah, there are a lot of ways to specify colors in a template.

All that said, px could just ignore most of that complexity and try to read from template.layout.colorway and template.layout.colorscale.sequential and call it a day 😃