Python Bokeh : Slider callback in ColumnDataSource not update

Question

我的回调有问题，我一切正常，除了图表没有更新的部分，即使当我更改 slider 时数组已更新。

import numpy as np

from bokeh.io import curdoc
from bokeh.layouts import row, widgetbox
from bokeh.models import ColumnDataSource, Slider
from bokeh.plotting import figure

data = {'x_values': [0,0,2,2,4,4],
        'y_values': [10,0,0,5,5,10]} #Seting up data

source = ColumnDataSource(data=data) # Map plot

plot = figure(title="Step Well",
              tools="save,wheel_zoom")

plot.line('x_values', 'y_values',source=source)

def update_data(attrname, old, new):
    Step = StepHeight.value

    x = [0,0,2,2,4,4]
    y = [10,0,0,Step,Step,10]
    source.data = ColumnDataSource(dict(x=x, y=y))
    source.on_change('value', update_data)

StepHeight = Slider(title="Step Height", 
                    value=4.0, 
                    start=2.0, end=6.0, step=0.2)
# Set up layouts and add to document
inputs = widgetbox(StepHeight)

layout = row(inputs, plot)

curdoc().title = "Sliders"
curdoc().add_root(layout)

Answer 1

您试图将 source.data 设为列数据源，但 source 应该是列数据源。 Source.data 只是一个字典。我更改了您的代码中的一些内容，现在应该可以正常工作了。

import numpy as np
from bokeh.io import curdoc
from bokeh.layouts import row, widgetbox
from bokeh.models import ColumnDataSource, Slider
from bokeh.plotting import figure

data = {'x_values': [0,0,2,2,4,4],
        'y_values': [10,0,0,5,5,10]} #Seting up data

source = ColumnDataSource(data=data) # Map plot

plot = figure(title="Step Well",
              tools="save,wheel_zoom")

plot.line('x_values', 'y_values',source=source)

def update_data(attrname, old, new):
    y = [10,0,0,new,new,10]
    source.data['y_values'] = y

StepHeight = Slider(title="Step Height", 
                    value=4.0, 
                    start=2.0, end=6.0, step=0.2)

StepHeight.on_change('value', update_data)

# Set up layouts and add to document
inputs = widgetbox(StepHeight)

layout = row(inputs, plot)

curdoc().title = "Sliders"
curdoc().add_root(layout)