I want a CheckboxGroup to represent different columns of a dataframe. The idea is for the user to be able to add multiple column values if they select multiple columns and interactively display the sum as a plot.
I have the following:
from bokeh.io import output_file, show
from bokeh.plotting import figure
from bokeh.layouts import layout, widgetbox
from bokeh.models import ColumnDataSource, CustomJS
from bokeh.models.widgets import CheckboxGroup, CheckboxButtonGroup, TextInput
import pandas as pd
output_file('additive_checkbox.html')
names = ['Number', 'A', 'B', 'C']
rows = [(340, 77, 70, 15),
(341, 80, 73, 15),
(342, 83, 76, 16),
(343, 86, 78, 17)]
data = pd.DataFrame(rows, columns=names)
data['combined'] = None
source = ColumnDataSource(data)
callback = CustomJS(args=dict(source=source), code="""
const labels = cb_obj.labels;
const active = cb_obj.active;
const data = source.data;
const sourceLen = data.combined.length;
const combined=Array(sourceLen).fill(undefined);
var combined_label = ''
if (active.length > 0) {
const selectedColumns = labels.filter((val, ind) => active.includes(ind));
for(let i = 0; i < sourceLen; i++) {
let sum = 0;
for(col of selectedColumns){
sum += data[col][i];
}
combined[i] = sum;
}
}
data.combined=combined;
source.change.emit();
""")
checkbox_group = CheckboxButtonGroup(labels=names[1:], active=[], js_event_callbacks=callback, width=400)
final_col = column(p, checkbox_group)
show(final_col)
And it is giving me the following error: ValueError: failed to validate CheckboxButtonGroup(id='1223', ...).js_event_callbacks: expected an element of Dict(String, List(Instance(CustomJS))), got CustomJS(id='1222', ...)
I am not good with JS and have no idea what it means!