python - 使用pandas的resample报错

问题描述

错误如下：

Traceback (most recent call last): File '<stdin>', line 1, in <module> File 'D:UsersAdministratorAnaconda2libsite-packagesspyderlibwidgetsexternalshellsitecustomize.py', line 699, in runfile execfile(filename, namespace) File 'D:UsersAdministratorAnaconda2libsite-packagesspyderlibwidgetsexternalshellsitecustomize.py', line 74, in execfile exec(compile(scripttext, filename, ’exec’), glob, loc) File 'C:/Users/Administrator/Documents/Python Scripts/untitled1.py', line 24, in <module> s3=s2.resample(’5min’, how=ohlc_dict, closed=’left’, label=’left’) File 'D:UsersAdministratorAnaconda2libsite-packagespandascoregeneric.py', line 4212, in resample base=base, key=on, level=level) File 'D:UsersAdministratorAnaconda2libsite-packagespandastseriesresample.py', line 944, in resample return tg._get_resampler(obj, kind=kind) File 'D:UsersAdministratorAnaconda2libsite-packagespandastseriesresample.py', line 1057, in _get_resampler 'but got an instance of %r' % type(ax).__name__)TypeError: Only valid with DatetimeIndex, TimedeltaIndex or PeriodIndex, but got an instance of ’Index’

我的代码如下：

names = [’date’, ’time’, ’open’, ’high’, ’low’, ’close’, ’vol’, ’amount’]s2=pd.read_csv(’E:/test/SZ399920.csv’,names=names, header=None, index_col=’date’)ohlc_dict = { ’open’:’first’,’high’:’max’, ’low’:’min’,’close’: ’last’,’vol’: ’sum’}s3=s2.resample(’5min’, how=ohlc_dict, closed=’left’, label=’left’)

dataframe文件的格式如下：

问题解答

你应该先把Index变成DatetimeIndex。你想resample到5分钟的话你也要把time放Index里：

df = pd.DataFrame({’date’: ['2008/07/01','2008/07/01','2008/07/01','2008/07/01','2008/07/01','2008/07/01','2008/07/01','2008/07/01'], ’time’: [’09:31’, ’09:32’,’09:33’,’09:34’,’09:35’,’09:36’,’09:37’, ’09:38’], ’vals’: [1, 2, 3, 4, 5, 6, 7, 8]})df2 = df.set_index(pd.DatetimeIndex(pd.to_datetime(df.date + ' ' + df.time)))df2.resample('5min', how={’vals’: ’mean’})