Three subplots in Python using the same data

Question

I'm currently needing some help here since I’m kinda novice. So I was able to import and plot my time series data via Pandas and Matplotlib, respectively. The thing is, the plot is too cramped up (due to the amount of data lol).

Using the same data set, is it possible to ‘divide’ the whole plot into 3 separate subplots?

Here's a sample to what I mean:

What I'm trying to do here is to distribute my plot into 3 subplots (it seems it doesn't have ncol=x).

Initially, my code runs like this;

import numpy as np
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker
import pandas as pd

pd.options.display.float_format = '{:,.4f}'.format
data = pd.read_csv ('all_visuallc.csv')   
df = pd.DataFrame(data, columns= ['JD', 'Magnitude'])
print(df) #displays ~37000ish data x 2 columns

colors = ('#696969') #a very nice dim grey heh
area = np.pi*1.7

ax = df.plot.scatter(x="JD", y="Magnitude", s=area, c=colors, alpha=0.2)
ax.set(title='HD 39801', xlabel='Julian Date', ylabel='Visual Magnitude')
ax.invert_yaxis()
ax.xaxis.set_minor_locator(ticker.AutoMinorLocator())
ax.yaxis.set_minor_locator(ticker.AutoMinorLocator())

plt.rcParams['figure.figsize'] = [20, 4]
plt.rcParams['figure.dpi'] = 250
plt.savefig('test_p.jpg')
plt.show()

which shows a very tight plot:

Thanks everyone and I do hope for your help and responses.

P.S. I think iloc[value:value] to slice from a df may work?

Elya Fadeeva · Accepted Answer · 2021-02-26 11:31:36Z

1

First of all, you have to create multiple plots for every part of your data. For example, if we want to split data into 3 parts, we will create 3 subplots. And then, as you correctly wrote, we can apply iloc (or another type of indexing) to the data.

Here is a toy example, but I hope you are be able to apply your decorations to it.

y = np.arange(0,20,1)
x = np.arange(20,40,1)
sample = pd.DataFrame(x,y).reset_index().rename(columns={'index':'y', 
0:'x'})

n_plots = 3
figs, axs = plt.subplots(n_plots, figsize=[30,10])
# Suppose we want to split data into equal parts
start_ind = 0
for i in range(n_plots):
    end_ind = start_ind + round(len(sample)/n_plots) #(*)
    part_of_frame = sample.iloc[start_ind:end_ind]
    axs[i].scatter(part_of_frame['x'], part_of_frame['y'])
    start_ind = end_ind

It's also possible to split data into unequal parts by changing the logic in the string (*)

edited Feb 26, 2021 at 11:31

answered Feb 20, 2021 at 10:29

Elya Fadeeva

1681 silver badge13 bronze badges

Sign up to request clarification or add additional context in comments.

8 Comments

CGHA Over a year ago

I do apologize for the late response. Nonetheless, it actually works. :) I got a small concern tho. One of the subplots (the bottom part) only contains the starting and end points data. While the rest of the data occupies the 1st and 2nd subplot. prnt.sc/101tnjd

CGHA Over a year ago

or I think it's because of the start and end_ind ^^

Elya Fadeeva Over a year ago

Thank you for finding a bug. Please, test it now:) I fixed the logic of finding indexes and the method of rounding. Now if the last part of frame is smaller than round(len(frame)/n_plots), it will be plotted correctly.

CGHA Over a year ago

Alright. It finally worked <3 Thanks a lot :D

Elya Fadeeva Over a year ago

I am very glad to help you :)

|

Collectives™ on Stack Overflow

Three subplots in Python using the same data

1 Answer 1

8 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

8 Comments

Your Answer

Sign up or log in

Post as a guest

Related