[使用一个命令在python matplotlib绘图中进行DRY处理

Question

import pandas as pd
import matplotlib.pyplot as plt

> importing csv files
january = pd.read_csv('divident_month/january.csv')
april = pd.read_csv('divident_month/april.csv')
july = pd.read_csv('divident_month/july.csv')
october = pd.read_csv('divident_month/october.csv')

> substracting column 'Open' to column close
jangain = january['Open']-january['Close']
aprgain = april['Open']-april['Close']
julgain = july['Open']-july['Close']
octgain = october['Open']-october['Close']

>plotting  
medium=[jangain, aprgain, julgain, octgain]
plt.plot(medium)
plt.show()

## jan = plt.plot(jangain, label='january')
## apr =plt.plot(aprgain, label='april')
## jul =plt.plot(julgain, label='july')
## oct =plt.plot(octgain, label='october')
## plt.legend()

我如何将多个项目绘制到图形中而不像##中那样重复自己。我在不同的月份有多个重复代码的文件（它们在div月份之前，div月份和div月份之后分为不同的文件）。

我已经尝试将它们分组为一个列表（中），然后将该列表传递到plt.plot(medium)但这似乎不起作用。

我还给出了地块名称（例如Jan，apr ...），因为我将其导入到不同的文件中以进行q1，q2，q3，q4分析（以防信息混淆）

这是我尝试使用python btw进行财务

Answer 1

您可以这样做：

import os
import pandas as pd, collections as co, matplotlib.pyplot as plt

the_dir = 'divident_month/'
months = co.OrderedDict() # use if order of csv files is important 

# iterate over files in directory
for a_file in sorted(os.listdir(the_dir)):
    if os.path.splitext(a_file)[-1] == '.csv':
        # add DataFrame entries to dictionary 
        months[a_file.rstrip('.csv')] = pd.read_csv(os.path.join(the_dir,a_file))

# perform gain calculation (k: dictionary `k`ey, v: dictionary `v`alue)
for k,v in months.items():
    months[k] = v['Open'] - v['Close']

# get an axes handle from matplotlib so you can re-use it
fig,ax = plt.subplots()

# plot without manual repetition of plot command
for k,v in months.items():
    ax = v.plot(ax=ax,label=k) 

# add title and show plot
plt.gcf().suptitle('Gain')
plt.show()