neko.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import matplotlib.pyplot as plt
import datetime
import numpy as np

plt.rcParams['font.family'] = 'sans-serif'
plt.rcParams['font.sans-serif'] = ['IPAPGothic', 'VL PGothic']

dt0 = datetime.date(1977,1,1)
dt1 = datetime.date(1977,10,20)
dt2 = datetime.date(1992,9,25)
dt3 = datetime.date(2001,3,1)
dt4 = datetime.date(2005,8,3)
dt5 = datetime.date(2021,1,6)

based = 1976
d0 = (dt1-dt0).days/365+based
d1 = (dt2-dt0).days/365+based
d2 = (dt3-dt0).days/365+based
d3 = (dt4-dt0).days/365+based
d4 = (dt5-dt0).days/365+based

year = [d0, d1 , d2, d3, d4]
ver = [1, 47, 71, 82, 120]
buy = ['初版','carma', 'tsunさん', 'rodydaddyさん','やみこさん']

av = round((ver[len(ver)-1] / year[len(year)-1] * 365),1)

plt.figure(facecolor="azure", edgecolor="coral", linewidth=1)
boxdic = {
    "facecolor" : "lightblue",
    "edgecolor" : "darkred",
    "boxstyle" : "Round",
    "linewidth" : 1
}

plt.plot(year, ver , marker="X")
plt.xticks(np.arange(1975, 2025, step=5))
for i, j in enumerate(year):
        plt.text(j+1, ver[i]-4, buy[i], color="blue")

plt.text(year[0], ver[4]-5, "年間平均刷数: " + str(av) + "刷", bbox=boxdic)        
plt.vlines(year, 0, ver , colors='red', linestyle='dashed', linewidth=1)
plt.title("『100万回生きたねこ』の刷数遷移")
plt.xlabel("発行年")
plt.ylabel("刷数")
plt.grid(True)

plt.show()