Anaconda Enterprise: Documentation

# interaction_callbacks_for_selections_lasso_mean.py

    from random import random
    from bokeh.models import CustomJS, ColumnDataSource
    from bokeh.plotting import figure, output_file, show

    output_file("callback.html")

    x = [random() for x in range(500)]
    y = [random() for y in range(500)]
    color = ["navy"] * len(x)

    s = ColumnDataSource(data=dict(x=x, y=y, color=color))
    p = figure(plot_width=400, plot_height=400, tools="lasso_select", title="Select Here")
    p.circle('x', 'y', color='color', size=8, source=s, alpha=0.4)

    s2 = ColumnDataSource(data=dict(x=[0, 1], ym=[0.5, 0.5]))
    p.line(x='x', y='ym', color="orange", line_width=5, alpha=0.6, source=s2)

    s.callback = CustomJS(args=dict(s2=s2), code="""
            var inds = cb_obj.selected['1d'].indices;
            var d = cb_obj.data;
            var ym = 0

            if (inds.length == 0) { return; }

            for (i = 0; i < d['color'].length; i++) {
                d['color'][i] = "navy"
            }
            for (i = 0; i < inds.length; i++) {
                d['color'][inds[i]] = "firebrick"
                ym += d['y'][inds[i]]
            }

            ym /= inds.length
            s2.data['ym'] = [ym, ym]

            cb_obj.change.emit();
            s2.change.emit();
        """)

    show(p)