Welcome toVigges Developer Community-Open, Learning,Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
1.1k views
in Technique[技术] by (71.8m points)

matplotlib - Pyplot sorting y-values automatically

I have a frequency analysis of words said in episodes of my favorite show. I'm making a plot.barh(s1e1_y, s1e1_x) but it's sorting by words instead of values. The output of >>> s1e1_y is

['know', 'go', 'now', 'here', 'gonna', 'can', 'them', 'think', 'come', 'time', 'got', 'elliot', 'talk', 'out', 'night', 'been', 'then', 'need', 'world', "what's"]

and >>>s1e1_x

[42, 30, 26, 25, 24, 22, 20, 19, 19, 18, 18, 18, 17, 17, 15, 15, 14, 14, 13, 13] When the plots are actually plotted, the graph's y axis ticks are sorted alphabetically even though the plotting list is unsorted...

s1e1_wordlist = []
s1e1_count = []
for word, count in s1e01:
    if((word[:-1] in excluded_words) == False):
        s1e1_wordlist.append(word[:-1])
        s1e1_count.append(int(count))
s1e1_sorted = sorted(list(sorted(zip(s1e1_count, s1e1_wordlist))), 
reverse=True)
s1e1_20 = []
for i in range(0,20):
    s1e1_20.append(s1e1_sorted[i])
s1e1_x = []
s1e1_y = []
for count, word in s1e1_20:
    s1e1_x.append(word)
    s1e1_y.append(count)
plot.figure(1, figsize=(20,20))
plot.subplot(341)
plot.title('Season1 : Episode 1')
plot.tick_params(axis='y',labelsize=8)
plot.barh(s1e1_x, s1e1_y)
See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

From matplotlib 2.1 on you can plot categorical variables. This allows to plot plt.bar(["apple","cherry","banana"], [1,2,3]). However in matplotlib 2.1 the output will be sorted by category, hence alphabetically. This was considered as bug and is changed in matplotlib 2.2 (see this PR).

In matplotlib 2.2 the bar plot would hence preserve the order. In matplotlib 2.1, you would plot the data as numeric data as in any version prior to 2.1. This means to plot the numbers against their index and to set the labels accordingly.

w = ['know', 'go', 'now', 'here', 'gonna', 'can', 'them', 'think', 'come', 
 'time', 'got', 'elliot', 'talk', 'out', 'night', 'been', 'then', 'need', 
 'world', "what's"]
n = [42, 30, 26, 25, 24, 22, 20, 19, 19, 18, 18, 18, 17, 17, 15, 15, 14, 14, 13, 13]

import matplotlib.pyplot as plt
import numpy as np

plt.barh(range(len(w)),n)
plt.yticks(range(len(w)),w)

plt.show()

enter image description here


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to Vigges Developer Community for programmer and developer-Open, Learning and Share
...