How to label points in a large scatterplot (~280k points)

Question

I have a scatterplot with about 280,000 points which displays quite nicely. However, I would like to dynamic labels to each point so that when I zoom into the graph enough I can see a bit of text on each point.

I've tried just using plt.annotate on every point, and on a smaller number of points

for index, row in points.iterrows():
    plt.annotate(row[0],  (row[1], row[2]))
    #if index+1 %100 == 0:
    #    break

This causes the window to lag and not actually display anything rather than display labels. If I uncomment the break then I still have a rather laggy window with a large black clump of overlapping text. If the text could only be displayed under a certain level of magnification, or even scale to be an appropriate size at different levels of magnification that would be great!

I'm really open to any solutions to create a labeled scatter plot from my data.

Answer 1

I was able to plot everything nicely with plotly like this, using plotly's Scattergl to speed everything up.

import plotly as plotly
py = plotly.offline
import plotly.graph_objs as go

trace = go.Scattergl(
    x = points['x'], 
    y = points['y'],
    text = points['word'], 
    mode = 'markers',
    marker = dict(
        color = '#FFBAD2',
        line = dict(width = 1)
    )
)

data = [trace]
layout = plotly.graph_objs.Layout(hovermode='closest')
figure = plotly.graph_objs.Figure(data=data, layout=layout)
py.plot(figure)