Select scatter plot marker size and colour values from dropdown

📊 Plotly Python
1

I’m trying to use the built in plotly widgets to select values for marker size and color in scatter and scatter_3d from plotly express. I can get this working using ipwidgets but then it resets the plot to the original orientation (3D). But when using updatemenus instead nothing changes at all.

Here’s an example code:

# stats is a pandas dataframe
 fig = px.scatter(stats, x='x', y='y',
                    color='cube num', size='Radius [mm] mean'                )
 fig.update_layout(scene_aspectmode='data')
 # fig.update_data(size='cube num')
 fig.update_layout(updatemenus=[
                     dict(
                         buttons=list([
                          dict(
                              args=[{'size':stats['cube num']},],
                              label='cube #',
                              method='update'
                          ),
                          dict(
                              args=[{'size':stats['Radius [mm] mean']},],
                              label='Average Radius',
                              method='update'
                          )         
                         ]),
                         showactive=True,
                         )                        
                      ]
                   
                     )
                  
 
 fig.show()

I’ve tried a number of variations to args and different methods.

2

@gawells
Your updatemenus definition has the following drawbacks:

  1. you called the update method, but here since your are updating only the trace attributes, you should set method='restyle'. (update method is called when you are re-setting both trace and layout attributes);
  2. to update marker size use the attribute marker.size, not just size;
  3. fig.data is a list of traces. In your case this list contains a single trace. When you are performing an update you must set the new values in a list (see https://chart-studio.plotly.com/~empet/15607/restyling-a-plotly-figure-via-a-dropdow/#/.
    Hence define the updatemenus as follows:
fig.update_layout(updatemenus=[
                     dict(
                         buttons=[
                          dict(
                              args=[{'marker.size': [stats['Radius [mm] mean']]}],
                              label='Average Radius',
                              method='update'
                          ),
                             dict(
                              args=[{'marker.size': [stats['cube num']]}],
                              label='cube #',
                              method='update'
                          )
                         ])
                        ]
                    )

Note that I reversed the buttons. The first one should set the size, as in fig.data[0] (just print(fig.data[0]).
Conclusion: to define updatemenus you must know how the corresponding fig.data is defined.