How to set scatter plot marker color in plotly express animations

📊 Plotly Python
1

I’m using px.scatter to create an animated dot plot that goes through the years with the play button.

fig = px.scatter(df, x="Rate", y="Country Name", color="Gender", animation_frame="Year",
                 range_x=[4,19], range_y=[-0.5,4.5]
      )

That works beautifully; however, I’m trying to change the default color of the markers for both genders (male,female).

If I run the script below:

fig.data[0]['marker'].update(color='#bff68e') #green
fig.data[1]['marker'].update(color='#fda026') #orange

the color changes correctly for both gender markers, but only for the FIRST frame. The subsequent frames go back to their default color. So I created a FOR loop to go over all the frames:

for x in fig.frames:
    x.data[0]['marker']['color'] = '#bff68e'
    x.data[1]['marker']['color'] = '#fda026'

This works fine. But I was wondering, Is there a faster and simpler way to update the marker color for all frames without creating a for loop?

2

@adamschroeder

If you are displaying fig.frames and see that each Frame.data has set the color['marker'], then you don’t have another faster solution than creating a loop. This means that the frame definition doesn’t update only the attributes of fig.data that change from frame to frame, but also the constant value attributes.

Usually if the fig data is defined like in this example:

fig = go.Figure()

fig.add_scatter(x=np.arange(10),
                         y=1+3*np.random.rand(10),
                         marker_size=6, marker_color='red', line_color='blue') #trace of index 2

and we want in each frame to change only point positions, not other properties, then the frames are defined as follows

fig.frames =  [go.Frame(data=[go.Scatter(y=2+3*np.random.rand(10))],
                                    traces=[0]) for k in range(20)]

Adding in Frame defintion the same color like in the corresponding fig.data is a superfluous setting.
I think that in the plotly express all fig.data settings are repeated in Frame definition, for generality, to let users customize the fig appearance after its definition

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