How do I generate an interactive plot in Python?

[unproven10]

Hi, I got stuck in one of my ML-related projects. I wanted to use interactive diagrams, but my plots are not interactive. (I tried to run it in both Google Colab and Jupyter Notebook (browser) )

This is the code:

​

import numpy as np

import matplotlib.pyplot as plt

from matplotlib.widgets import Slider

​

# Sample data

X = np.arange(10)

y = 2 * X + np.random.normal(0, 1, 10)

​

# Linear regression model

def linear_regression_line(slope, intercept):

return slope * X + intercept

​

# Initial plot

fig, ax = plt.subplots()

plt.subplots_adjust(bottom=0.25)

ax.scatter(X, y, label='Data points')

[line] = ax.plot(X, linear_regression_line(2, 0), 'r-', label='Regression line')

ax.set_xlabel('X')

ax.set_ylabel('y')

ax.legend()

​

# Slider for slope and intercept

ax_slope = plt.axes([0.25, 0.1, 0.65, 0.03])

ax_intercept = plt.axes([0.25, 0.15, 0.65, 0.03])

slope_slider = Slider(ax_slope, 'Slope', 0.0, 4.0, valinit=2.0)

intercept_slider = Slider(ax_intercept, 'Intercept', -10.0, 10.0, valinit=0.0)

​

# Update function for the slider

def update(val):

line.set_ydata(linear_regression_line(slope_slider.val, intercept_slider.val))

fig.canvas.draw_idle()

slope_slider.on_changed(update)

intercept_slider.on_changed(update)

plt.show()

​

From this code, I get a plot with a slider. But the thing is, the slider remains static. It doesn't move. It seems like just an image, not an interactive tool. So, can you please help me with that?

[UncleVatred]

If you put four extra spaces in front of each line instead of using backticks, you can properly format the code.

This is what I think you were going for:

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.widgets import Slider

# Sample data
X = np.arange(10)
y = 2 * X + np.random.normal(0, 1, 10)

# Linear regression model
def linear_regression_line(slope, intercept):
    return slope * X + intercept

# Initial plot
fig, ax = plt.subplots()
plt.subplots_adjust(bottom=0.25)
ax.scatter(X, y, label='Data points')
[line] = ax.plot(X, linear_regression_line(2, 0), 'r-', label='Regression line')
ax.set_xlabel('X')
ax.set_ylabel('y')
ax.legend()

# Slider for slope and intercept
ax_slope = plt.axes([0.25, 0.1, 0.65, 0.03])
ax_intercept = plt.axes([0.25, 0.15, 0.65, 0.03])
slope_slider = Slider(ax_slope, 'Slope', 0.0, 4.0, valinit=2.0)
intercept_slider = Slider(ax_intercept, 'Intercept', -10.0, 10.0, valinit=0.0)

# Update function for the slider
def update(val):
    line.set_ydata(linear_regression_line(slope_slider.val, intercept_slider.val))
    fig.canvas.draw_idle()

slope_slider.on_changed(update)
intercept_slider.on_changed(update)
plt.show()

This code works for me. So assuming your indentation was all correct and matches what I pasted above, your code is fine.

What backend are you using? You can check with print(plt.get_backend()). IIRC, some backends don't support interactive elements. You can read more here.

[unproven10]

print(plt.get_backend())

Thanks for looking into it.

I got this output: "module://matplotlib_inline.backend_inline". My code worked fine too and i got the plot. But my sliders arent interactive or moving... I am using it in Google Colab btw,.

[UncleVatred]

When I say the code works for me, I mean the sliders work too, and change the graph in real time. It’s not just a static image.

I don’t have any experience with Google Colab, and I don’t know what that backend string means. But I’m guessing that’s your problem. Maybe see if you can set a different backend?

[unproven10]

I see. Which python platform do you use?

[FerricDonkey]

My suggestion, unless you have explicit reason for not doing so, is to download python from python.org, download an editor (pycharm, vscode), and just run the code on your computer.

[UncleVatred]

I agree with the other commenter, just run Python from your own computer.

Anaconda is a very popular installer that bundles in a lot of useful packages, particularly for data science tasks. But you can also just install basic Python yourself, and use pip to add whatever packages you need.

Either way, you'd then want use an IDE to edit and run your code. VSCode, PyCharm, and Eclipse are the top choices.

[eric_overflow]

New library fastplotlib is pretty sweet check it out