legend markers are not rendered in scatter plot

[ledmonster]

I got a similar issue with scatter plot as #185. But framealpha hack is not effective here.

import numpy as np
import matplotlib.pyplot as plt
import mpld3

%matplotlib inline

mpld3.enable_notebook()

fig, ax = plt.subplots()
ax.scatter(np.random.randn(10), np.random.randn(10), color="red", label="data1")
ax.scatter(np.random.randn(10), np.random.randn(10), color="blue", label="data2")
ax.legend(title="Cluster", loc="best", framealpha=0)

It seems that svg has g elements for markers, but they are not rendered in legend. Are there something wrong with my code?

[jakevdp]

Looks like a bug. If you come up with a fix, contributions are welcome!

[teffland]

Don't know if this is addressed at all, but in case anyone else needs a work around and only cares about showing the colors for certain labels in the legend (so it is at least worth something), I've been setting the font colors with

    l = ax.legend(fancybox=0)
    for i, text in enumerate(l.get_texts()):
        text.set_color(colors[i])

[sangaline]

Another more direct workaround is to leave the labels off of the scatter plots and then plot empty arrays with ax.plot() to populate the legend. So instead of

fig, ax = plt.subplots()
ax.scatter(np.random.randn(10), np.random.randn(10), color="red", label="data1")
ax.scatter(np.random.randn(10), np.random.randn(10), color="blue", label="data2")
ax.legend(title="Cluster", loc="best", framealpha=0)

you can do

fig, ax = plt.subplots()
ax.scatter(np.random.randn(10), np.random.randn(10), color="red")
ax.plot([], [], "o", color="red", label="data1")
ax.scatter(np.random.randn(10), np.random.randn(10), color="blue")
ax.plot([], [], "o", color="blue", label="data2")
ax.legend(title="Cluster", loc="best", framealpha=0)

and the legend will include the colored markers.

[deepyaman]

mpld3/mplexporter#54 should fix this issue!