How To Use The Output Of One Bokeh Widget As An Input In Another Widget Through A Callback Function?

I have a dataframe with some random characteristics (factors) for some companies. I would like to select one factor in the first widget and then the min and the max value of the se

Solution 1:

Because a DataFrame is not serializable you have to pass its columns separately in the list format. I tested the code in Bokeh v1.1.0.

import math
import numpy as np
import pandas as pd
import random
import matplotlib.pyplot as plt
from bokeh.plotting import figure, output_file, show
from bokeh.models import ColumnDataSource, HoverTool, CustomJS
from bokeh.sampledata.autompg import autompg_clean as df
from bokeh.models.widgets import Slider, Select, TextInput, RangeSlider, DataTable, TableColumn
from bokeh.layouts import layout, column

CompanyList = ['00', '01', '02', '03']

a = pd.DataFrame({
    'Factor1' : [random.randint(0, 10) for t in range(4)],
    'Factor2' : [random.randint(0, 100) for t in range(4)],
    'Factor3' : [random.randint(0, 1000) for t in range(4)],
    'CompanyNo' : CompanyList})

a = a.set_index('CompanyNo')

C1 = Select(title = "Constraint 1", options = sorted(list(a.columns)), value = 'Factor1')
R1 = RangeSlider(title = "Range Constraint 2", value = (a[C1.value].min(), a[C1.value].max()), start = a[C1.value].min(), end = a[C1.value].max(), step = 0.1, width = 300)

C1.callback = CustomJS(args = dict(R1 = R1, C1 = C1, Factor1 = a['Factor1'].values, Factor2 = a['Factor2'].values, Factor3 = a['Factor3'].values), code = """
    array = eval(C1.value)
    R1.start = Math.min(...array);                  
    R1.end = Math.max(...array);
    R1.value = [Math.min(...array), Math.max(...array)];    
    """)

show(column(C1, R1))