python pandas slice columns

pandas import Series,dataf The Rame#numpy element progression group method also applies to pandas object frame = DataFrame (Np.random.randn (4,3), columns = List (' abc '), index = [' Ut ', ' Oh ', ' Te ', ' Or ']) print frame# The following is the absolute value: #print Np.abs (frame) #另一种常见的做法是: Apply a function to a row or column, using the Apply method, like

namePrint Food_info.columns #打印dataframe数据类型下的各列列名.5) Dataframe sample number and number of indicatorsPrint Food_info.shape #打印dataframe形状, a few rows of columns, where the number of rows is the number of samples, the number of columns is the number of indicators.6) Pandas fetch dataFetch data by sample (ROW):Pandas d

is sometimes possible to replace missing data with 0, but this is not always the casePrint ("zero filled\n", Df.fillna (0))Pivot tablePivotTables can aggregate data from rows and columns specified in a flat file, which can be summed, averaged, and standard poor operationsSince the pandas API has provided us with the top-level pivot_table () function and the corresponding Dataframe method, you can let this

way, and filtering through a Boolean array.However, it is important to note that because the index of the Pandas object is not limited to integers, it is included at the end when using a non-integer as the tile index.>>> fooa 4.5b 7.2c -5.3d 3.6dtype:float64>>> bar0 4.51 7.22 -5.33 3.6dtype:float64>>> foo[:2]a 4.5b 7.2dtype:float64>>> bar[:2]0 4.51 7.2dtype:float64>>> foo[: ' C ']a 4.5b 7.2c -5.3dtype:float64

The following for you to share a Python data Analysis Library Pandas basic operation method, has a good reference value, I hope to help you. Come and see it together. What is Pandas? Is it it? 。。。。 Apparently pandas is not so cute as this guy .... Let's take a look at how Pandas's official website defines itself:

data (like select in SQL):DataFrame #从pandas库中引用DataFrameDf_obj = DataFrame () #创建DataFrame对象Df_obj.dtypes #查看各行的数据格式Df_obj.head () #查看前几行的数据, default first 5 rowsDf_obj.tail () #查看后几行的数据, default after 5 rowsDf_obj.index #查看索引Df_obj.columns #查看列名Df_obj.values #查看数据值Df_obj.describe #描述性统计Df_obj. T #转置Df_obj.sort (columns = ") #按列名进行排序Df_obj.sort_index (by=[","]) #多列排序, use the Times this function is obsole

This article mainly introduces how to use Python pandas framework to operate data in Excel files, including basic operations such as unit format conversion and classification and Summarization. For more information, see Introduction The purpose of this article is to show you how to use pandas to execute some common Excel tasks. Some examples are trivial, but I t

the original value, which is different from ndarry, for example, the drop line after the call to the original object, found that there is no change　　　　　　Drop column: Obj4.drop (' Nevada ', Axis=1)In the parameters of many functions of Python, the default is to consider row, so there is axis (axis) This parameter　　　　　　Axis=1 is vertical, that is, the columnAxis=0 is a horizontal,　　4.2 Select selection, slice