Python Pandas - 格式化 PeriodIndex 对象的字符串表示形式
要格式化PeriodIndex对象的字符串表示形式，请使用该方法。将格式说明符设置为参数。periodIndex.strftime()
首先，导入所需的库-
import pandas as pd
创建一个PeriodIndex对象。PeriodIndex是一个不可变的ndarray，其中包含指示定期时间段的序数值-
periodIndex = pd.PeriodIndex(['2021-09-25 07:30:35', '2019-10-30 04:15:45', '2020-07-15 02:55:15', '2022-06-25 09:40:55'], freq="Y")
显示PeriodIndex对象-
print("PeriodIndex...\n", periodIndex)显示格式化结果-
print("\nString representation (format with different directives)...\n",
periodIndex.strftime('%b. %d, %Y was a %A'))示例
以下是代码-
import pandas as pd
#CreateaPeriodIndexobject
#PeriodIndexisanimmutablendarrayholdingordinalvaluesindicatingregularperiodsintime
# We have set the frequency using the "freq" parameter
periodIndex = pd.PeriodIndex(['2021-09-25 07:30:35', '2019-10-30 04:15:45',
'2020-07-15 02:55:15', '2022-06-25 09:40:55'], freq="Y")
#DisplayPeriodIndexobject
print("PeriodIndex...\n", periodIndex)
#DisplayPeriodIndexfrequency
print("\nPeriodIndex frequency object...\n", periodIndex.freq)
#DisplayPeriodIndexfrequency as string
print("\nPeriodIndex frequency object as a string...\n", periodIndex.freqstr)
#displaytheformattedresult
print("\nString representation (format with different directives)...\n",
periodIndex.strftime('%b. %d, %Y was a %A'))输出结果这将产生以下代码-
PeriodIndex... PeriodIndex(['2021', '2019', '2020', '2022'], dtype='period[A-DEC]') PeriodIndex frequency object... <YearEnd: month=12> PeriodIndex frequency object as a string... A-DEC String representation (format with different directives)... Index(['Dec. 31, 2021 was a Friday', 'Dec. 31, 2019 was a Tuesday', 'Dec. 31, 2020 was a Thursday', 'Dec. 31, 2022 was a Saturday'], dtype='object')