Python Matplotlib how to plot multiple graph in the same figure

Question

This is my code

import matplotlib.pyplot as plt
import matplotlib.animation as animation

from matplotlib import style

style.use('fivethirtyeight')


def animate(i):
    graph_data = open('data.txt','r').read()
    lines = graph_data.split('\n')
    xs = []
    ys = []

    for line in lines:
        if len(line) > 1:
            x, y = map(int, line.split(','))
            xs.append(x)
            ys.append(y)
    ax1.clear()
    ax1.plot(xs,ys)

fig = plt.figure()
ax1 = fig.add_subplot(1,1,1)

ani = animation.FuncAnimation(fig, animate, interval=30000)
plt.show()

data.txt and data2.txt are just like:

Now I have another data2.txt file and I need to plot the graph in the same figure like "overlapping". How to do this with this code?

Hi Botticelli69. Welcome to StackOverflow. Could you please edit your question and paste files: data.txt and data2.txt ? The better your question is, the easier it gets for someone to answer it. Please read: https://stackoverflow.com/help/how-to-ask — greenmarker, Jun 21 '20 at 12:19
Does this answer your question? [How to plot multiple functions on the same figure, in Matplotlib?](https://stackoverflow.com/questions/22276066/how-to-plot-multiple-functions-on-the-same-figure-in-matplotlib) — Deepthought, Jun 21 '20 at 12:42

Sameeresque · Accepted Answer · 2020-06-21T15:56:32.980

You can make use of matplotlib's interactive mode by invoking plt.ion(). Assuming your files are named in the format data {data1, data2, data3..}, store them as a list using glob. You can then get overlapping lines read from the different files as shown here:

import numpy as np
import matplotlib.pyplot as plt
from matplotlib import style
import glob

style.use('fivethirtyeight')
#data files stored as a list in files
files=glob.glob('*data*')

fig, ax = plt.subplots()
plt.ion()
plt.show()

for i in files:
    x,y = np.loadtxt(i,unpack=True,delimiter=',')
    line = ax.plot(x,y,label=i)
    plt.gcf().canvas.draw()
    plt.legend(loc=2)
    plt.pause(1)

Yes it works! But I need the graph to stay rather than disappear after 1 second, and it need to process data in real time — Botticelli69, Jun 22 '20 at 12:21

Python Matplotlib how to plot multiple graph in the same figure

1 Answers1