[Resolved] Valid modes for plotly_selected

plotly.js
1

After some experimentation with the select event plotly_selected, I’ve noticed that
x: x_values,
y: y_values,
type: ‘scatter’,
mode: ‘markers’

allows the user to select points on the plot. However,
x: x_values,
y: y_values,
type: ‘scatter’,
mode: ‘lines’

Does not return any values after the event. (If you remove mode: 'lines', it looks like type: 'scatter' defaults to mode: 'lines' and so removing it doesn’t solve the issue.)

For my plot, I need to allow the user to select the points drawn up (as lines). This seems to be an issue, so my questions:

  1. For which modes are plotly_selected currently supported
  2. If plotly_selected currently supports mode: 'lines', what can I do to get my code to work?

I apologize if this has already been asked somewhere. I’ve been unable to locate it if it has.

Thank you in advance

2

That’s correct. Selection aren’t supported on lines yet. See https://github.com/plotly/plotly.js/issues/170#issuecomment-317063282 for more info.

3

Thanks @etienne

Here’s a workaround for anybody else that encounters the same problem.

When defining your data, define mode: 'lines+markers' and set a marker size

For example,

{
   name: 1,
   x: x,
   y: x,
   type: 'scatter',
   mode: 'lines+markers',
   marker: {
      size: 0.01,
   }
}

Then the plotly_selected will work. It’ll pick up the markers, but with the marker size so low the user won’t see the markers. I’m sure this increases overhead, but it does work.

4 
{
   name: 1,
   x: x,
   y: x,
   type: 'scatter',
   mode: 'lines+markers',
   marker: {
      opacity: 0
   }
}

should perform even better.

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