Markers in Holoviews

Question

The following script produces a nice scatterplot as in the picture below

from holoviews import extension, dim, opts, Scatter
from pandas import read_csv
extension('bokeh')
url = 'https://raw.githubusercontent.com/mwaskom/seaborn-data/master/penguins.csv'
df = read_csv(url)
scatterplot = Scatter(df, 'flipper_length_mm', ['body_mass_g','island'] )
scatterplot.opts( color=dim('island').str(), cmap=['red','green','blue'] )

Now, suppose I want to use markers in place of colors for island.

Is there something equivalent to cmap (as in the last line of the script above) for marker?

Answer 1

You can update the code as below to add markers. I have left the colors as is. If you don't need it, can remove that and just keep the markers alone... You can use markers from here

scatterplot.opts( color=dim('island').str(), cmap=['red','green','blue'],
                 marker=dim('island').categorize({'Torgersen':'circle', 'Biscoe':'diamond', 'Dream':'dash'}) )