Python 如何在dataframe中取出列索引名
如何删除上面数据框中的日期索引名?它应该与其他列名在同一行中,但它不是导致问题的列名Python 如何在dataframe中取出列索引名,python,pandas,Python,Pandas,如何删除上面数据框中的日期索引名?它应该与其他列名在同一行中,但它不是导致问题的列名 谢谢简短回答:你不能,也不清楚为什么这会“造成问题”。“日期”名称用于命名数据框的索引,它不同于任何列。它是用这个偏移量打印出来的,这样你就不会把它和框架的一列混淆了。您不会使用DataFrame['date']按如下方式分割日期: Open High Low Close Volume Adj Close Date
谢谢简短回答:你不能,也不清楚为什么这会“造成问题”。“日期”名称用于命名数据框的索引,它不同于任何列。它是用这个偏移量打印出来的,这样你就不会把它和框架的一列混淆了。您不会使用
DataFrame['date']
按如下方式分割日期:
Open High Low Close Volume Adj Close
Date
1990-01-02 00:00:00 35.25 37.50 35.00 37.25 6555600 8.70
1990-01-03 00:00:00 38.00 38.00 37.50 37.50 7444400 8.76
1990-01-04 00:00:00 38.25 38.75 37.25 37.63 7928800 8.79
1990-01-05 00:00:00 37.75 38.25 37.00 37.75 4406400 8.82
1990-01-08 00:00:00 37.50 38.00 37.00 38.00 3643200 8.88
在此之后,您可以简单地更改索引的名称,以便不打印任何内容:
>>> dfrm['Date'] = dfrm.index
>>> dfrm
A B C Date
Date
2012-06-01 0.283724 0.863012 0.798891 2012-06-01
2012-06-02 0.097231 0.277564 0.872306 2012-06-02
2012-06-03 0.821461 0.499485 0.126441 2012-06-03
2012-06-04 0.887782 0.389486 0.374118 2012-06-04
2012-06-05 0.248065 0.032287 0.850939 2012-06-05
2012-06-06 0.101917 0.121171 0.577643 2012-06-06
2012-06-07 0.225278 0.161301 0.708996 2012-06-07
2012-06-08 0.906042 0.828814 0.247564 2012-06-08
2012-06-09 0.733363 0.924076 0.393353 2012-06-09
2012-06-10 0.273837 0.318013 0.754807 2012-06-10
这似乎有点过分了。另一种选择是在将日期添加为列后,将索引更改为整数或其他内容:
>>> dfrm.reindex(pandas.Series(dfrm.index.values, name=''))
A B C Date
2012-06-01 0.283724 0.863012 0.798891 2012-06-01
2012-06-02 0.097231 0.277564 0.872306 2012-06-02
2012-06-03 0.821461 0.499485 0.126441 2012-06-03
2012-06-04 0.887782 0.389486 0.374118 2012-06-04
2012-06-05 0.248065 0.032287 0.850939 2012-06-05
2012-06-06 0.101917 0.121171 0.577643 2012-06-06
2012-06-07 0.225278 0.161301 0.708996 2012-06-07
2012-06-08 0.906042 0.828814 0.247564 2012-06-08
2012-06-09 0.733363 0.924076 0.393353 2012-06-09
2012-06-10 0.273837 0.318013 0.754807 2012-06-10
或者,如果已经手动将索引移动到列中,则只需
>>> dfrm.reset_index()
或者,如果您关心列的显示顺序,请执行以下操作:
>>> dfrm.index = range(len(dfrm))
>>> dfrm
A B C Date
0 0.283724 0.863012 0.798891 2012-06-01
1 0.097231 0.277564 0.872306 2012-06-02
2 0.821461 0.499485 0.126441 2012-06-03
3 0.887782 0.389486 0.374118 2012-06-04
4 0.248065 0.032287 0.850939 2012-06-05
5 0.101917 0.121171 0.577643 2012-06-06
6 0.225278 0.161301 0.708996 2012-06-07
7 0.906042 0.828814 0.247564 2012-06-08
8 0.733363 0.924076 0.393353 2012-06-09
9 0.273837 0.318013 0.754807 2012-06-10
已添加
下面是一些有用的函数,可以包含在iPython配置脚本中(以便在启动时加载它们),或者放在使用Python时可以轻松加载的模块中
>>> dfrm.ix[:,[-1]+range(len(dfrm.columns)-1)]
Date A B C
0 2012-06-01 0.283724 0.863012 0.798891
1 2012-06-02 0.097231 0.277564 0.872306
2 2012-06-03 0.821461 0.499485 0.126441
3 2012-06-04 0.887782 0.389486 0.374118
4 2012-06-05 0.248065 0.032287 0.850939
5 2012-06-06 0.101917 0.121171 0.577643
6 2012-06-07 0.225278 0.161301 0.708996
7 2012-06-08 0.906042 0.828814 0.247564
8 2012-06-09 0.733363 0.924076 0.393353
9 2012-06-10 0.273837 0.318013 0.754807
我还在下面制作了一个类来保存一些普通股的数据:
###########
# Imports #
###########
import pandas
import datetime
import numpy as np
from dateutil import relativedelta
from pandas.io import data as pdata
############################################
# Functions to retrieve Yahoo finance data #
############################################
# Utility to get generic stock symbol data from Yahoo finance.
# Starts two days prior to present (or most recent business day)
# and goes back a specified number of days.
def getStockSymbolData(sym_list, end_date=datetime.date.today()+relativedelta.relativedelta(days=-1), num_dates = 30):
dReader = pdata.DataReader
start_date = end_date + relativedelta.relativedelta(days=-num_dates)
return dict( (sym, dReader(sym, "yahoo", start=start_date, end=end_date)) for sym in sym_list )
###
# Utility function to get some AAPL data when needed
# for testing.
def getAAPL(end_date=datetime.date.today()+relativedelta.relativedelta(days=-1), num_dates = 30):
dReader = pdata.DataReader
return getStockSymbolData(['AAPL'], end_date=end_date, num_dates=num_dates)
###
尝试使用
reset\u index
方法,将数据帧的索引移动到列中(我想这是您想要的)。非常感谢,我正在使用循环从yahoo finance加载数据,当我尝试df=DataFrame(data1)时,它给我一个错误,说我必须传递一个索引错误:ValueError:如果使用所有标量值,则必须通过索引“。循环使用DataReader获取数据,并将其放入名为data1的dict中。是的,我编写了一些实用程序函数,可以直接使用我的IPython配置脚本加载,其中许多函数对于通过Pandas快速获取Yahoo数据、将其放入数据帧以及计算原始价格数据的二次统计信息非常有用。不幸的是,它正在工作,但我可以稍后添加helper函数。这正是我想要做的。听起来不错,我怎么能在它完成后再查看呢?我将发布一条评论,这样它就应该在左侧放置一个红色通知交易。如果已经过了几天,我已经忘记了,你也可以发表评论。
###########
# Imports #
###########
import pandas
import datetime
import numpy as np
from dateutil import relativedelta
from pandas.io import data as pdata
############################################
# Functions to retrieve Yahoo finance data #
############################################
# Utility to get generic stock symbol data from Yahoo finance.
# Starts two days prior to present (or most recent business day)
# and goes back a specified number of days.
def getStockSymbolData(sym_list, end_date=datetime.date.today()+relativedelta.relativedelta(days=-1), num_dates = 30):
dReader = pdata.DataReader
start_date = end_date + relativedelta.relativedelta(days=-num_dates)
return dict( (sym, dReader(sym, "yahoo", start=start_date, end=end_date)) for sym in sym_list )
###
# Utility function to get some AAPL data when needed
# for testing.
def getAAPL(end_date=datetime.date.today()+relativedelta.relativedelta(days=-1), num_dates = 30):
dReader = pdata.DataReader
return getStockSymbolData(['AAPL'], end_date=end_date, num_dates=num_dates)
###
#####
# Define a 'Stock' class that can hold simple info
# about a security, like SEDOL and CUSIP info. This
# is mainly for debugging things and quickly getting
# info for a single security.
class MyStock():
def __init__(self, ticker='None', sedol='None', country='None'):
self.ticker = ticker
self.sedol=sedol
self.country = country
###
def getData(self, end_date=datetime.date.today()+relativedelta.relativedelta(days=-1), num_dates = 30):
return pandas.DataFrame(getStockSymbolData([self.ticker], end_date=end_date, num_dates=num_dates)[self.ticker])
###
#####
# Make some default stock objects for common stocks.
AAPL = MyStock(ticker='AAPL', sedol='03783310', country='US')
SAP = MyStock(ticker='SAP', sedol='484628', country='DE')