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Python Graphs and Charts

Posted by Pattarakorn Tussanapirom
Pattarakorn Tussanapirom
2,467 Points

Graph not show

I have followed steps given in the video but graph is still not show up. My output is <function __main__.update (f, w=1, A=1, phi=0)>

2 Answers

Megan Amendola
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STAFF
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Megan Amendola
Treehouse Teacher
Megan Amendola
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Megan Amendola
Treehouse Teacher

Hi! Did you enable JavaScript to run in your notebook? Kenneth shows how to do this in the video starting at about 1:38. The code to run in your terminal is in the teacher's notes.

Jessica Dobson
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Jessica Dobson
Data Analysis Techdegree Graduate 33,377 Points
Jessica Dobson
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Jessica Dobson
Data Analysis Techdegree Graduate 33,377 Points

I have the same output as above, but running the code in the teacher's notes doesn't work because I'm in Jupyter 7 and it just keeps saying nbextenstion not found.

Sharina Jones
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Sharina Jones
Data Analysis Techdegree Student 6,697 Points
Sharina Jones
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Sharina Jones
Data Analysis Techdegree Student 6,697 Points

Installing Visualization Libraries

You can install the necessary packages using either pip or conda:

Using pip (inside or outside a notebook):

!pip install numpy bokeh panel

Or using conda:

conda install numpy bokeh -c conda-forge
conda install panel -c pyviz

Once installed, restart your Jupyter kernel to ensure the libraries are available.

Enabling Panel in JupyterLab

Panel works out of the box in JupyterLab version 3 and later (including version 4.3.4). You do not need to enable extensions manually. Just make sure you initialize it in your notebook with:

import panel as pn
pn.extension()

Creating an Interactive Plot with Panel and Bokeh

Paste the following code into a new notebook cell to create an interactive wave plot:

import numpy as np
import panel as pn
from bokeh.plotting import figure
from bokeh.io import output_notebook

pn.extension()
output_notebook()

# Create initial data
x = np.linspace(0, 2 * np.pi, 2000)
y = np.sin(x)

# Set up the plot
p = figure(title='Interactive Wave Plot', height=300, width=600, y_range=(-5, 5))
r = p.line(x, y, color='navy', line_width=3)

# Define the update function
def update(f="sin", w=1, A=1, phi=0):
    func = {"sin": np.sin, "cos": np.cos, "tan": np.tan}[f]
    r.data_source.data['y'] = A * func(w * x + phi)

# Create widgets
f_widget = pn.widgets.Select(name='Function', options=["sin", "cos", "tan"], value="sin")
w_widget = pn.widgets.IntSlider(name='Frequency (w)', start=0, end=100, value=1)
A_widget = pn.widgets.IntSlider(name='Amplitude (A)', start=1, end=5, value=1)
phi_widget = pn.widgets.FloatSlider(name='Phase (phi)', start=0, end=20, step=0.1, value=0)

# Bind widgets to function
pn.bind(update, f=f_widget, w=w_widget, A=A_widget, phi=phi_widget)

# Layout and display
layout = pn.Row(pn.Column(f_widget, w_widget, A_widget, phi_widget), p)
layout

This layout uses Panel to create a live-updating graph of sine, cosine, and tangent waves. You can control the frequency, amplitude, and phase using sliders, and switch wave types using a dropdown menu.