如何在Matplotlib X轴中显示日期而不是序列号

Question

I am trying to develop a candlestick chart with matplotlib but for some reason, dates are not coming up in the x-axis. After searching in stackoverflow, I understood that the dates need to be converted to float numbers so i converted them as well but still it's not working. New to this python and matplotlib. ANy help would be greatly appreciated.

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.finance import candlestick2_ohlc
import matplotlib.dates as dts
import matplotlib.ticker as mTicker
from datetime import datetime
my_file=pd.read_csv("C:\\path\\to\\file\\file.csv",sep=",",names=['Date','Open','High','Low','Close','AdjClose','Volume'],skiprows=1)
dateseries=[]
for i in my_file['Date']:
    dateseries.append(dts.date2num(datetime.strptime(i,'%Y-%m-%d')))
print(dateseries)
fig,ax1=plt.subplots()
candlestick2_ohlc(ax1,my_file['Open'], my_file['High'],my_file['Low'],     my_file['Close'], width=0.7,colorup='#008000', colordown='#FF0000')
plt.show()

Sample data:

Date,Open,High,Low,Close,Volume1,Volume2
2017-05-08,149.029999,153.699997,149.029999,153.009995,153.009995,48752400
2017-05-09,153.869995,154.880005,153.449997,153.990005,153.990005,39130400
2017-05-10,153.630005,153.940002,152.110001,153.259995,153.259995,25805700

Answer 1

In general, you are right about "the dates need to be converted to float numbers". Then to display dates on x-axis, you would need to "convert" them back. If you don't mind using candlestick_ohlc , that might be easier for setting the x-axis for your case here:

import io

import matplotlib.pyplot as plt
from matplotlib.finance import candlestick_ohlc
from matplotlib.dates import date2num, DayLocator, DateFormatter
import pandas as pd

s = """Date,Open,High,Low,Close,Volume1,Volume2
2017-05-08,149.029999,153.699997,149.029999,153.009995,153.009995,48752400
2017-05-09,153.869995,154.880005,153.449997,153.990005,153.990005,39130400
2017-05-10,153.630005,153.940002,152.110001,153.259995,153.259995,25805700"""
my_file = pd.read_table(io.StringIO(s), sep=',', header=0)

my_file['Date'] = date2num(pd.to_datetime(my_file['Date']).tolist())

fig, ax=plt.subplots()
candlestick_ohlc(ax, my_file.as_matrix())
ax.xaxis.set_major_locator(DayLocator())
ax.xaxis.set_major_formatter(DateFormatter('%Y-%m-%d'))
plt.show()