Joel Ostblom

There are situations like the below that raises the error although the same data is technically used, just respecified as a new variable. ```py alt.layer( alt.Chart(data.movies.url).mark_rule().encode(x='IMDB_Rating:Q'), alt.Chart(data.movies.url).mark_rule().encode(x='IMDB_Rating:Q') ).facet( 'Major_Genre:N' )...

Should JupyterCharts fire a callback when the selection changes?

10

I'm experimenting with using Altair together with the Shiny dashboarding framework for Python, and thanks to the JupyterChart widget that @jonmmease added it seems like this is working out of...

Describe hovering and z-order reordering in interactive docs

2

Include an example of how to bring points to top when hovered as here https://github.com/vega/vega-lite/pull/9136

More convenient syntax instead of `FieldOneOfPredicate`

10

Writing a condition that matches a single value in relatively straightforward: ```py import altair as alt from vega_datasets import data source = data.cars() alt.Chart(source).mark_point().encode( x='Horsepower', y='Miles_per_Gallon', color=alt.condition( alt.datum.Origin == 'Japan',...

Include autocompletion for column names

7

Follow up from discussion with @binste in https://github.com/altair-viz/altair/pull/3208#issuecomment-1742136253. It would be helpful to enable autocompletion of column names when doing `.encode(x=` and/or `alt.X(`. pandas already autocompletes column names when you...

I think it would be helpful to show how to create a small dashboard / data app with ipywidgets and the new JupyterChart. I'm thinking something similar to what I...

I think a powerful feature of altair is to create small self contained data apps / dashboards that can be shared as an html page. This is great as it...

`alt.datum` and `alt.value` generates incorrect error messages

2

Originally reported in https://github.com/altair-viz/altair/pull/2883#issuecomment-1427383912. When using the datum encoding then the message is incorrect: ```py alt.Chart().mark_point().encode(x=alt.datum(1, wrong_name=1)) ``` ``` SchemaValidationError: Invalid specification altair.vegalite.v5.schema.channels.X, validating 'additionalProperties' Additional properties are not allowed...

Support extension/addon mechanism for creating custom marks

3

I think it would be really helpful if it was possible to create custom marks outside altair/vega-lite that would be accessible through separate packages. `ggplot` has a similar mechanism where...

This has led to some confusion in the past and has been discussed a bit in https://github.com/altair-viz/altair/issues/2520#issuecomment-977858965 by @mattijn and @jakevdp. I recently ran into this again in https://github.com/hex-inc/vegafusion/issues/381#issuecomment-1705543712 where...