slider.py¶

import numpy as np

from bokeh.layouts import row, widgetbox
from bokeh.models import CustomJS, Slider
from bokeh.plotting import figure, output_file, show, ColumnDataSource

x = np.linspace(0, 10, 500)
y = np.sin(x)

source = ColumnDataSource(data=dict(x=x, y=y))

plot = figure(y_range=(-10, 10), plot_width=400, plot_height=400)

plot.line('x', 'y', source=source, line_width=3, line_alpha=0.6)

callback = CustomJS(args=dict(source=source), code="""
    var data = source.data;
    var A = amp.value;
    var k = freq.value;
    var phi = phase.value;
    var B = offset.value;
    x = data['x']
    y = data['y']
    for (i = 0; i < x.length; i++) {
        y[i] = B + A*Math.sin(k*x[i]+phi);
    }
    source.change.emit();
""")

amp_slider = Slider(start=0.1, end=10, value=1, step=.1,
                    title="Amplitude", callback=callback)
callback.args["amp"] = amp_slider

freq_slider = Slider(start=0.1, end=10, value=1, step=.1,
                     title="Frequency", callback=callback)
callback.args["freq"] = freq_slider

phase_slider = Slider(start=0, end=6.4, value=0, step=.1,
                      title="Phase", callback=callback)
callback.args["phase"] = phase_slider

offset_slider = Slider(start=-5, end=5, value=0, step=.1,
                       title="Offset", callback=callback)
callback.args["offset"] = offset_slider

layout = row(
    plot,
    widgetbox(amp_slider, freq_slider, phase_slider, offset_slider),
)

output_file("slider.html", title="slider.py example")

show(layout)